BIOLOGY 

RA 

6 


A 


TREATISE 


ON 


ANATOMY,   PHYSIOLOGY, 
AND  HYGIENE:- 


DESIGNER  FOR 


COLLEGES,  ACADEMIES,  AND  FAMILIES. 


BY  CALVIN  CUTTER,  M.D. 


WITH  ONE  HUNDRED  AND   Fl 


REVISED 


NEW   YORK: 
CLARK,    AUSTIN     AND     SMITH. 

CINCINNATI  :—  W.  B.  SMITH  &  CO. 
ST.  LOUIS,  MO.:—  KEITH  &  WOODS. 

1858. 


0  ?3 


Enterea  according  to  Act  of  Congress,  in  tne  year  1852,  b> 

CALVIN    CUTTER,  M.JD., 
In  the  Clerk's  Office  of  the  District  Court  of  the  District  of  Massachusetts. 


C.  A.  ALVORD,  PKINTBB, 
No.  1  i  Vandewater  Street,  N.  Y 


PREFACE. 


AGESILAUS,  king  of  Sparta,  when  asked  what  things  boys 
should  learn,  replied,  "  Those  which  they  will  practise  when 
they  become  men."  As  health  requires  the  observance  of 
the  laws  inherent  to  the  different  organs  of  the  human  system, 
so  not  only  boys,  but  girls,  should  acquire  a  knowledge  of  the 
laws  of  their  organization.  If  sound  morality  depends  .ipon 
the  inculcation  of  correct  principles  in  youth,  equally  so  does 
a  sound  physical  system  depend  on  a  correct  physical  edu- 
cation during  the  same  period  of  life.  If  the  teacher  and 
parents  who  are  deficient  in  moral  feelings  and  sentiments, 
are  unfit  to  communicate  to  children  and  youth  those  high 
moral  principles  demanded  by  the  nature  of  man,  so  are  they 
equally  incompetent  directors  of  the  physical  training  of  the 
youthful  system,  if  ignorant  of  the  organic  laws  and  the  phys- 
iological conditions  upon  which  health  and  disease  depend. 

For  these  reasons,  the  study  of  the  structure  of  the  human 
system,  and  the  laws  of  the  different  organs,  are  subjects  of 
interest  to  all,  —  the  young  and  the  old,  the  learned  and  the 
unlearned,  the  rich  and  the  poor.  Every  scholar,  and  particu- 
larly every  young  miss,  after  acquiring  a  knowledge  of  the 
primary  branches,  —  as  spelling,  reading,  writing,  and  arith- 
metic,—  should  learn  the  structure  of  the  human  system,  and 
1  * 


6  PREFACE. 

th°  conditions  upon  which  health  and  disease  depend,  as  this 
Knowledge  will  be  required  in  practice  in  after  life. 

"  It  is  somewhat  unaccountable,"  says  Dr.  Dick,  "  and  not 
a  fittle  inconsistent,  that  while  we  direct  the  young  to  look 
abroad  over  the  surface  of  the  earth,  and  survey  its  moun- 
tains, rivers,  seas,  and  continents,  and  guide  their  views  to 
the  regions  of  the  firmament,  where  they  may  contemplate 
the  moons  of  Jupiter,  the  rings  of  Saturn,  and  thousands  of 
luminaries  placed  at  immeasurable  distances,  *  *  that  we 
should  never  teach  them  to  look  into  themselves ;  to  consider 
their  own  corporeal  structures,  the  numerous  parts  of  which 
they  are  composed,  the  admirable  functions  they  perform,  the 
wisdom  and  goodness  displayed  in  their  mechanism,  and  the 
lessons  of  practical  instruction  which  may  be  derived  from 
such  contemplations." 

Again  he  says,  "  One  great  practical  end  which  should 
always  be  kept  in  view  in  the  study  of  physiology,  is  the 
invigoration  and  improvement  of  the  corporeal  powers  and 
functions,  the  preservation  of  health,  and  the  prevention  of 
disease." 

The  design  of  the  following  pages  is,  to  diffuse  in  the 
community,  especially  among  the  youth,  a  knowledge  of 
Human  Anatomy,  Physiology,  and  Hygiene.  To  make 
the  work  clear  and  practical,  the  following  method  has 
been  adopted :  — 

1st.  The  structure  of  the  different  organs  of  the  system 
has  been  described  in  a  clear  and  concise  manner.  To 
render  this  description  more  intelligible,  one  hundred  and 
fifty  engravings  have  been  introduced,  to  show  the  situation 
of  the  various  organs.  Hence  the  work  may  be  regarded 
as  an  elementary  treatise  on  anatomy. 


PREFACE.  7 

2d.  The  functions,  or  uses  of  the  several  parts  have  been 
briefly  and  plainly  detailed ;  making  a  primary  treatise  on 
human  physiology. 

3d.  To  make  a  knowledge  of  the  structure  and  functions 
of  the  different  organs  practical,  the  laws  of  the  several 
parts,  and  the  conditions  on  which  health  depends,  have 
been  clearly  and  succinctly  explained.  Hence  it  may  be 
called  a  treatise  on  the  principles  of  hygiene,  or  health. 

To  render  this  department  more  complete,  there  has  been 
added  the  appropriate  treatment  for  burns,  wounds,  hemor- 
rhage from  divided  arteries,  the  management  of  persons 
asphyxiated  from  drowning,  carbonic  acid,  or  strangling, 
directions  for  nurses,  watchers,  and  the  removal  of  disease, 
together  with  an  Appendix,  containing  antidotes  for  poisons, 
so  that  persons  may  know  what  should  be  done,  and  what 
should  not  /be  done,  until  a  surgeon  or  physician  can  be 
called. 

In  attempting  to  effect  this  in  a  brief  elementary  treatise 
designed  for  schools  and  families,  it  has  not  been  deemed 
necessary  to  use  vulgar  phrases  for  the  purpose  of  being 
understood.  The  appropriate  scientific  term  should  be  applied 
to  each  organ.  No  more  effort  is  required  to  learn  the  mean 
ing  of  a  proper,  than  an  improper  term.  For  example :  a 
child  will  pronounce  the  word  as  readily,  and  obtain  as 
correct  an  idea,  if  you  say  lungs,  as  if  you  used  the  word 
lights.  A  little  effort  on  the  part  of  teachers  and  parents, 
would  diminish  the  number  of  vulgar  terms  and  phrases,  and, 
consequently,  improve  the  language  of  our  country.  To 
obviate  all  objections  to  the  use  of  proper  scientific  terms,  a 
Glossary  has  been  appended  to  the  work. 


8  PREFACE. 

The  author  makes  no  pretensions  to  new  discoveries  ID 
physiological  science.  In  preparing  the  anatomical  depart- 
ment, the  able  treatises  of  Wilson,  Cruveilhier,  and  others 
have  been  freely  consulted.  In  the  physiological  part,  the 
splendid  works  of  Carpenter,  Dunglison,  Liebig,  and  others 
have  been  perused.  In  the  department  of  hygiene  many 
valuable  hints  have  been  obtained  from  the  meritorious 
works  of  Combe,  Rivers,  and  others. 

We  are  under  obligations  to  R.  D.  Mussey,  M.  D.,  formerly 
Professor  of  Anatomy  and  Surgery,  Dartmouth  College, 
N.  H.,  now  Professor  of  Surgery  in  the  Ohio  Medical  Col- 
lege ;  to  J.  E.  M'Girr,  A.  M.,  M.  D.,  Professor  of  Anatomy, 
Physiology,  and  Chemistry,  St.  Mary's  University,  111.  ;  to 
E.  Hitchcock,  Jr.,  A.  M.,  M.  D.,  Teacher  of  Chemistry  and 
Natural  History,  Williston  Seminary,  Mass. ;  to  Rev.  E.  Hitch- 
cock, D.  D.,  President  of  Amherst  College,  Mass.,  who  examined 
the  revised  edition  of  this  work,  and  whose  valuable  suggestions 
rendered  important  aid  in  preparing  the  manuscript  for  the 
present  stereotype  edition. 

We  return  our  acknowledgments  for  the  aid  afforded  by  the 
Principals  of  the  several  Academies  and  Normal  Schools  who 
formed  classes  in  their  institutions,  and  examined  the  revised 
edition  as  their  pupils  progressed,  thus  giving  the  work  the 
best  possible  test  trial,  namely,  the  recitation-room. 

To  the  examination  of  an  intelligent  public,  the  work  is 
respectfully  submitted  by 

CALVIN  CUTTER. 

WARREN,  MASS.,  Sept.  1,  1852. 


TO   TEACHERS   AND   PARENTS. 


As  the  work  is  divided  into  chapters,  the  subjects  of 
which  are  complete  in  themselves,  the  pupil  may  com- 
mence the  study  of  the  structure,  use,  and  laws  of  the 
several  parts  of  which  the  human  system  is  composed, 
by  selecting  such  chapters  as  fancy  or  utility  may  dic- 
tate, without  reference  to  their  present  arrangement, 
— as  well  commence  with  the  chapter  on  the  digestive 
organs  as  on  the  bones. 

The  acquisition  of  a  correct  pronunciation  of  the 
technical  words  is  of  great  importance,  both  in  recita- 
tion and  in  conversation.  In  this  work,  the  technical 
words  interspersed  with  the  text,  have  been  divided 
mto  syllables,  and  the  accented  syllables  designated. 
An  ample  Glossary  of  technical  terms  has  also  been 
appended  to  the  work,  to  which  reference  should  be 
made. 

It  is  recommended  that  the  subject  be  examined  in 
the  form  of  topics.  The  questions  in  Italics  are  de- 
signed for  this  method  of  recitation.  The  teacher 
may  call  on  a  pupil  of  the  class  to  describe  the  anal 
omy  of  an  organ  from  an  anatomical  outline  plate  ; 
afterwards  call  upon  another  to  give  the  physiology 
of  the  part,  while  a  third  may  state  the  hygiene,  after 


10  TO  TEACHERS  AND  PARENTS. 

which,  the  questions  at  the  bottom  of  the  page  may 
be  asked  promiscuously,  and  thus  the  detailed  knowl- 
edge of  the  subject  possessed  by  the  pupils  will  be 
tested. 

At  the  close  of  the  chapters  upon  the  Hygiene  of 
the  several  portions  of  the  system,  it  is  advised  that 
the  instructor  give  a  lecture  reviewing  the  anatomy, 
physiology,  and  hygiene,  of  the  topic  last  considered. 
This  may  be  followed  by  a  general  examination  of 
the  class  upon  the  same  subject.  By  this  course  a 
clear  and  definite  knowledge  of  the  mutual  relation  of 
the  Anatomy,  Physiology,  and  Hygiene,  of  different 
parts  of  the  human  body,  will  be  presented. 

We  also  suggest  the  utility  of  the  pupils'  giving 
analogous  illustrations,  examples,  and  observations, 
where  these  are  interspersed  in  the  different  chap- 
ters, not  only  to  induce  inventive  thought,  but  to 
discipline  the  mind. 

To  parents  and  others  we  beg  leave  to  say,  that 
about  two  thirds  of  the  present  work  is  devoted  to  a 
concise  and  practical  description  of  the  uses  of  the 
important  organs  of  the  human  body,  and  to  show 
how  such  information  may  be  usefully  applied,  both 
in  the  preservation  of  health,  and  the  improvement  of 
physical  education.  To  this  have  been  added  direc- 
tions for  the  treatment  of  those  accidents  which  are 
daily  occurring  in  the  community,  making  it  a  treatise 
proper  and  profitable  for  the  FAMILY  LIBRARY,  as  well 
as  the  school-room. 


CONTENTS. 


Cbtpter.  Pt.ga 

1.  GENERAL  REMARKS, 13 

2.  STRUCTURE  or  MAN , 17 

3.  CHEMISTRY  OF  THE  HUMAN  BODY 25 

4.  ANATOMY  OP  THE  BONES, . .  29 

5.  ANATOMY  OP  THE  BONES,  CONTINUED, 39 

6.  PHYSIOLOGY  OF  THE  BONES, 48 

7.  HYGIENE  OF  THE  BONES, 53 

8.  ANATOMY  OP  THE  MUSCLES, 64 

9.  PHYSIOLOGY  OF  THE  MUSCLES, 76 

10.  HYGIENE  OF  THE  MUSCLES, 85 

11.  HYGIENE  OF  THE  MUSCLES,  CONTINUED, 96 

12.  ANATOMY  OF  THE  TEETH, 105 

12.  PHYSIOLOGY  OF  THE  TEETH, 109 

12.  HYGIENE  OF  THE  TEETH, 110 

13.  ANATOMY  OF  THE  DIGESTIVE  ORGANS, 113 

14.  PHYSIOLOGY  OF  THE  DIGESTIVE  ORGANS, 124 

15.  HYGIENE  OF  THE  DIGESTIVE  ORGANS, 129 

16.  HYGIENE  OF  THE  DIGESTIVE  ORGANS,  CONTINUED, 142 

17.  ANATOMY  OF  THE  CIRCULATORY  ORGANS, 154 

18.  PHYSIOLOGY  OF  THE  CIRCULATORY  ORGANS 164 

19.  HYGIENE  OF  THE  CIRCULATORY  ORGANS, 172 

20.  ANATOMY  OF  THE  LYMPHATIC  VESSELS, 181 

20.  PHYSIOLOGY  OF  THE  LYMPHATIC  VESSELS 183 

20.  HYGIENE  OF  THE  LYMPHATIC  VESSELS, 188 

21.  ANATOMY  OF  THE  SECRETORY  ORGANS,.-. 192 

21.   PHYSIOLOGY  OF  THE   SECRETORY  ORGANS, 193 

21.  HYGIENE  OF  THE  SECRETORY  ORGANS, 197 

22.  NUTRITION, 200 

22.  HYGIENE  OF  NUTRITION,  •. 205 

23.  ANATOMY  OF  THE  RESPIRATORY  ORGANS, 209 


I*  CONTENTS. 

Chapter.  pAg9 

24.  PHYSIOLOGY  OF  THE  RESPIRATORY  ORGANS, 217 

25.  HYGIENE  OF  THE  RESPIRATORY  ORGANS 228 

26.  HYGIENE  OF  THE  RESPIRATORY  ORGANS,  CONTINUED, 239 

27.  ANIMAL  HEAT,. 252 

28.  HYGIENE  OF  ANIMAL  HEAT, 261 

29.  ANATOMY  OF  THE  VOCAL  ORGANS, 268 

29.  PHYSIOLOGY  OF  THE  VOCAL  ORGANS, 272 

30.  HYGIENE  OF  THE  VOCAL  ORGANS, 274 

31.  ANATOMY  OF  THE  SKIN 282 

32.  PHYSIOLOGY  OF  THE  SKIN, 293 

83    HYGIENE  OF  THE  SKJN, 301 

34.  HYGIENE  OF  THE   SKIN,  CONTINUED, 311 

35.  APPENDAGES  OF  THE  SKIN, 322 

36.  ANATOMY  OF  THE  NERVOUS  SYSTEM, 327 

37.  ANATOMY  OF  THE  NERVOUS  SYSTEM,  CONTINUED, 340 

38.  PHYSIOLOGY  OF  THE  NERVOUS  SYSTEM, 346 

39.  HYGIENE  OF  THE  NERVOUS  SYSTEM, 358 

40.  HYGIENE  OF  THE  NERVOUS  SYSTEM,  CONTINUED, 368 

41.  THE   SENSE  OF  TOUCH, 378 

42.  ANATOMY  OF  THE  ORGANS  OF  TASTE, 384 

42.  PHYSIOLOGY  OF  THE  ORGANS  OF  TASTE, 386 

43.  ANATOMY  OF  THE  ORGANS  OF  SMELL, 389 

43.  PHYSIOLOGY  OF  THE  ORGANS  OF  SMELL, 391 

44.  ANATOMY  OF  THE  ORGANS  OF  VISION, 394 

45.  PHYSIOLOGY  OF  THE  ORGANS  OF  VISION, 404 

45.  HYGIENE  OF  THE  ORGANS  OF  VISION, 410 

46.  ANATOMY  OF  THE  ORGANS  OF  HEARING, 414 

47.  PHYSIOLOGY  OF  THE  ORGANS  OF  HEARING, 420 

47.  HYGIENE  OF  THE  ORGANS  OF  HEARING, 422 

48.  MEANS  OF  PRESERVING  THE  HEALTH, 425 

49.  DIRECTIONS  FOB  NUBSES, 432 


APPENDIX 439 

GLOSSARY, 451 

INDEX, 463 


ANATOMY,    &c. 


CHAPTER    I. 

GENERAL    REMARKS. 

1.  ANATOMY  is  the  science  which  treats  of  the  structure 
and  relations  of  the  different  parts  of  animals  and  plants. 

2.  It  is  divided  into  Vegetable  and  Animal  anatomy.     The 
latter  of  these  divisions  is  subdivided  into  Human  anatomy, 
which  considers,  exclusively,  human  beings  ;  and  Comparative 
anatomy,  which  treats  of  the  mechanism  of  the  lower  orders 
of  animals. 

3.  PHYSIOLOGY  treats  of  the  functions,  or  uses  of  the  organs 
of  animals  and  plants.     Another  definition  is,  "  the  science  of 
life." 

4.  This  is  also  divided  into  Vegetable  and  Animal  physiol- 
ogy, as  it  treats  of  the  vegetable  or  animal  kingdom ;  and 
into  Human  and  Comparative  physiology,  as  it  describes  the 
vital  functions  of  man  or  the  inferior  animals. 

5.  HYGIENE  is  the  art  or  science  of  maintaining  health,  01 
a  knowledge  of  those  laws  by  which  health  may  be  preserved. 

6.  The  kingdom  of  nature  is  divided  into  organic  and  in- 
organic bodies.     Organic  bodies  possess  organs,   on  whose 

1.  What  is  anatomy  1  2.  How  is  it  divided  1  How  is  the  latter  division 
otibdivided  1  3.  What  is  physiology  1  Give  another  definition.  4.  How  is 
physiology  divided  t  Give  a  subdivision.  5.  What  is  hygiene  ?  6.  Define 
organic  bodies. 

2 


14  ANATOMY,    PHYSIOLOGY,    ANI    HYGIENE. 

action  depend  their  growth  and  perfection.  This  divii  i 
ncludes  animals  and  plants.  Inorganic  bodies  are  de*  oid  :>f 
organs,  or  instruments  of  life.  In  this  division  are  classed 
the  earths,  metals,  and  other  minerals. 

7.  In  general,  organic   matter  differs  so  materially  from 
inorganic,  that  the  one  can  readily  be  distinguished  from  the 
other.     In  the  organic  world,  every  individual  of  necessity 
springs  from    some  parent,  or  immediate  producing  agent ; 
for   while    inorganic    substances    are    formed    by   chemical 
laws  alone,  we  see  no  case  of  an  animal  or  plant  coming 
into  existence   by  accident  or   chance,  or   chemical   opera 
tions. 

8.  Animals  and  plants  are  supported  by  means  of  nourish- 
ment, and  die  without  it.     They  also  increase  in  size  by  the 
addition  of  new  particles  of  matter  to  all  parts  of  their  sub- 
stances ;  while  rocks  and  minerals  grow  only  by  additions  tc 
their  surfaces. 

9.  "  Organized   bodies  always  present  a  combination  of 
both  solids  and  fluids  ;  —  of  solids,  differing  in  character  and 
properties,  arranged  into  organs,   and   these    endowed  with 
functional  powers,  and  so  associated  as  to  form  of  the  whole 
a  single  system  ;  —  and  of  fluids,  contained  in  these  organs, 
and   holding  such  relation  to  the   solids  that  the   existence, 
nature,  and  properties  of  both  mutually  and  necessarily  de- 
pend on  each  other." 

10.  Another  characteristic  is,  that  organic  substances  have 
a  certain  order  of  parts.     For  example,  plants  possess  organs 
to  gain  nourishment  from  the  soil  and  atmosphere,  and  the 
power  to  give  strength  and  increase  to  all  their  parts.     And 
animals  need  not  only  a  digesting  and  circulating  apparatus, 
but  organs  for  breathing,  a  nervous  system,  &c. 

Define  inorganic  bodies.  7.  What  is  said  of  the  difference,  in  general,  be- 
tween organic  and  inorganic  bodies  ?  8.  What  of  the  growth  of  organic  and 
inorganic  bodies  ?  9.  What  do  organized  bodies  always  present  ?  10.  Give 
another  characteristic  of  organized  substances. 


GENERAL  REMARKS: 

11.  Individuality  is  an  important  characteristic.     For  in- 
stance, a  large  rock  may  be  broken  into  a  mmber  of  smaller 
pieces,  and  yet  every  fragment  will  be  rock ;  but  if  an  or- 
ganic substance   be  separated    into  two  or   more    divisions, 
neither  of  them  can  be  considered  an  individual.      Closely 
associated  with  this  is  the  power  of  life,  or  vitality,  which  is 
the  most  distinguishing  characteristic  of  organic  structure  ; 
since  we  find  nothing  similar  to  this  in  the  inorganic  creation. 

12.  The  distinction  between  plants  and  animals  is  also  of 
much   importance.      Animals    grow  proportionally   in    all 
directions,  while  plants  grow  upwards  and  downwards  from  a 
collet  only.     The  food  of  animals  is  organic,  while  that  of 
plants  is  inorganic ;  the  latter  feeding  entirely  upon  the  ele- 
ments of  the  soil  and  atmosphere,  while  the  former  subsist 
upon   the   products  of  the  animal  and  vegetable  kingdoms. 
The  size  of  the  vegetable  is  in  most  cases  limited  only  by  the 
duration  of  existence,  as  a  tree  continues  to  put  forth  new 
branches  during  each  period  of  its  life,  while  the  animal,  at  a 
certain  time  of  life,  attains  the  average  size  of  its  species. 

13.  One   of  the   most  important  distinctions  between  ani- 
mals and  plants,  is  the  different  effects  of  respiration.     Ani- 
mals consume  the  oxygen  of  the  atmosphere,  and  give  off 
carbonic  acid ;  while  plants  take  up  the  carbonic  acid,  and 
restore  to  animals  the  oxygen,  thus  affording  an  admirable 
example  of  the  principle  of  compensation  in  nature. 

14.  But   the    decisive    distinctions    between   animals   and 
plants  are  sensation  and  voluntary  motion,  the  power  of  ac- 
quiring a  knowledge  of  external  objects  through  the  senses, 
and  the  ability  to  move  from  place  to  place  at  will.     These 

11.  What  is  said  of  the  individuality  of  organized  and  inorganized  bodies? 
What  is  closely  associated  with  this  1  12.  Give  a  distinction  between  ani 
mals  and  plants  as  regards  growth.  The  food  of  animals  and  plants.  What 
is  said  in  respect  to  size  ?  13.  What  important  distinction  in  the  effects  of 
respiration  of  animals  and  plants  ?  14.  What  are  the  decisive  distinctions 
between  animals  and  plants '/ 


16  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

are  the  characteristics  which,  in  their  fullest  development  in 
man,  show  intellect  and  reasoning  powers,  and  thereby  m  a 
greater  degree  exhibit  to  us  the  wisdom  and  goodness  of  the 
Creator. 

15.  DISEASE,  which  consists  in  an  unnatural  condition  of  the 
bodily  organs,  is  in  most  cases  under  the  control  of  fixed  laws, 
which  we  are  capable  of  understanding  and  obeying.     Nor 
do  diseases  come  by  chance ;  they  are  penalties  for  violating 
physical  laws.     If  we  carelessly  cut  or  bruise  our  flesh,  pain 
•ind  soreness  follow,  to  induce  us  to  be  more  careful  in  the 
future ;  or,  if  we  take  improper  food  into  the  stomach,  we 
are  warned,  perhaps  immediately  by  a  friendly  pain,  that  we 
have  violated  an  organic  law. 

16.  Sometimes,  however,  the  penalty  does  not  directly  fol- 
low the  sin,  and  it  requires  great  physiological  knowledge  to 
be  able  to  trace  the  effect  to  its  true  cause.     If  we  possess 
good  constitutions,  we  are  responsible  for  most  of  our  sick- 
ness ;  and  bad  constitutions,  or  hereditary  diseases,  are  but 
the  results  of  the  same   great  law,  —  the  iniquities  of  the 
parents  being  visited  on  the  children.     In  this  view  of  the 
subject.,  how  important  is  the  study  of  physiology  and  hygiene  ! 
For  how  can  we  expect  to  obey  laws  which  we  do  not  under- 
stand ? 


15.   What  is  said  of  disease  ?     16.   Why  is  the  study  of  physiology  and 
tygiene  important? 


STRUCTURE    OF    MAN.  IT 


CHAPTER     II. 

STRUCTURE    OF    MAN. 

17.  IN  the  structure  of  the  human  body,  there  is  a  union 
of  fluids  and  solids.     These  are  essentially  the  same,  for  the 
one  is  readily  changed  into  the  other.     There  is  no  fluid  that 
does  not  contain  solid  matter  in  solution,  and  no  solid  matter 
that  is  destitute  of  fluid. 

18.  In  different  individuals,  and  at  different  periods  of  life 
the  proportion  of  fluids  and  solids  varies.     In  youth,  the  fluids 
are  more  abundant  than  in  advanced  life.     For  this  reason, 
the  limbs  in  childhood  are  soft  and  round,  while  in  old  age 
they  assume  a  hard  and  wrinkled  appearance. 

19.  The  fluids  not  only  contain  the  materials  from  which 
every  part  of  the  body  is  formed,  but  they  are  the  medium 
for  conveying  the  waste,  decayed  particles  of  matter  from  the 
system.      They  have  various  names,  according  to  their  nature 
and  function ;   as,  the  blood,  and  the  bile. 

20.  The  solids  are  formed  from  the  fluids,  and  consequent- 
ly they  are  reduced,  by  chemical  analysis,  to  the  same  ultimate 
elements.      The    particles  of  matter  in  solids  are  arranged 
variously;    sometimes  \nftbres,  (threads,)  sometimes  in  lam'i- 
nce,  (plates,)  sometimes  homogeneously,  as  in  basement  mem. 
branes.     (Appendix  A.) 

21.  The  parts  of  the  body  are  arranged  into  Fi'bres,  Fa» 
cic'u-H)  Tis'sues,  Or'gans,  Ap-pa-ra'tus-es,  and  Sys'tems. 

17.  What  substances  enter  into  the  structure  of  the  human  body  ?  Are 
they  essentially  the  same  ?  18.  What  is  said  of  these  substances  a.t  differ- 
ent periods  of  life  ?  19.  What  offices  do  the  fluids  of  the  system  perform  ? 
20.  What  is  said  of  the  solids  ?  How  are  the  particles  of  matter  ar 
ranged  in  (?olids  ?  21.  Give  an  arrangement  of  the  parts  of  the  body. 
2* 


18  ANATOMY,    PHYSIOLOGY    AND   HYGIENE. 

22.  A  FIBRE  is  a  thread  of  exceeding  fineness.     It  is  either 
cylindriform  or  flattened. 

23.  A  FASCICULUS  is  the  term  applied  to  several   fibres 
united.     Its  general  characteristics  are  the  same  as  fibres. 

24.  A  TISSUE  is  a  term  applied  to  several  different  solids 
of  the  body. 

25.  An  ORGAN  is  composed  of  tissues  so  arranged  as  to 
form  an  instrument  designed  for  action.     The  action  of  an 
organ  is  called  its  function,  or  use. 

Example.     The  liver  is  an  organ,  and  the  secretion  of  the 
bile  from  the  blood  is  one  of  its  functions.* 

26.  An  APPARATUS  is  an  assemblage  of  organs  designed 
to  produce  certain  results. 

Example.     The  digestive  apparatus  consists  of  the  teeth 
stomach,  liver,  &c.,  all  of  which  aid  in  the  digestion  of  food. 

Fig.  2. 


Fig.  2.  Represents  a  portion  of  broken  muscular  fibre  of  animal  lite,  (magnified 
tbout  seven  hundred  diameters.) 

27.  The  term  SYSTEM  is  applied  to  an  assemblage  of 
organs  arranged  according  to  some  plan,  or  method ;  as  the 
nervous  system,  the  respiratory  system. 

*  Where  examples  and  observations  are  given  or  experiments 
suggested,  let  the  pupil  mention  other  ^.alogous  ones. 

22.  Define  a  fibre.  23.  Define  a  fasciculus.  24.  Define  a  tissue.  25.  De- 
fine an  organ.  What  is  the  action  of  an  organ  called  ?  Give  examples. 
Mention  other  examples.  26.  What  is  an  apparatus  ?  Give  an  example 
27.  How  is  the  term  system  applied  ? 


STRUCTURE    OF    MAN.  19 

28.  A  TISSUE  is  a  simple  form  of  organized  animal  sub- 
stance.    It  is  flexible,  and  formed  of  fibres  interwoven  in 
various  ways  ;  as,  the  cellular  tissue. 

29.  However  various  all  organs  may  appear  in  their  struc- 
ture and  composition,  it  is  now  supposed  that  they  can  be 
reduced  to  a  few  tissues  ;  as,  the  Cel'lu-lar,  Os'se-ous,  Mus'cu- 
lar,  Mu'cous,  Nervous,  &c.     (Appendix  B.) 

30.  The  CELLULAR  TISSUE,*  now  called  the  areolar  tissue, 
consists  of  small  fibres,  or  bands,  interlaced  in  every  direc- 
tion, so  as  to  form  a  net-work,  with  numerous  interstices  that 
communicate  freely  with  each  other.     These  interstices  are 
filled,  during  life,  with  a  fluid  resembling  the  serum  of  blood. 
The  use  of  the  areolar  tissue  is  to  connect  together  organs 
and  parts  of  organs,  and  to  envelop,  fix,  and  protect  the  ves- 
sels and  nerves  of  organs. 

Fig.  3. 


Fig.  3.    Arrangement  of  fibres  of  the  cellular  tissue  magnified  one  hundred  and 
thirty  diameters. 

Observations.  1st.  When  this  fluid  becomes  too  great  in 
quantity,  in  consequence  of  disease,  the  patient  labors  under 
general  dropsy.  The  swelling  of  the  feet  when  standing,  and 
their  return  to  a  proper  shape  during  the  night,  so  often 
noticed  in  feeble  persons,  furnish  a  striking  proof  both  of  the 


*  The  Cellular,  Serous,  Dermoid,  Fibrous,  and  Mucous  tissues  are 
very  generally  called  membranes. 

28.  What  is  a  tissue  ?  29.  What  is  said  respecting  the  structure  and  com 
position  of  the  various  organs  ?  Name  the  primary  membranes.  30.  De 
scribe  the  cellular  tissue.  How  are  the  cells  imbedded  in  certain  tissues  ? 
Give  observation  1st,  relative  to  the  cellular  tissue 


20  ANATOMY,    PHYSIOLOGY,   AND   HYGIENE. 

existence  and  peculiarity  of  this  tissue,  which  allows  the 
fluid  to  flow  from  cell  to  cell,  until  it  settles  in  the  lower  ex- 
tremities. 

2d.  The  free  communication  between  the  cells  is  still 
more  remarkable  in  regard  to  air.  Sometimes,  when  an  ac- 
cidental opening  has  been  made  from  the  air-cells  of  the 
lungs  into  the  contiguous  cellular  tissue,  the  air  in  respiration 
has  penetrated  every  part  until  the  whole  body  is  so  inflated 
as  to  occasion  suffocation.  Butchers  often  avail  themselves 
of  the  knowledge  of  this  fact,  and  inflate  their  meat  to  give  it 
a  fat  appearance. 

31.  "  Although  this  tissue  enters  into  the  composition  of  all 
organs,  it  never  loses  its  own  structure,  nor  participates  in  the 
functions  of  the  organ  of  which  it  forms  a  part.     Though 
present  in  the  nerves,  it  does  not  share  in  their  sensibility ; 
and  though  it  accompanies  every  muscle  and  every  muscular 
fibre,  it  does  not  partake  of  the  irritability  which  belongs  to 
these  organs." 

32.  Several  varieties  of  tissue  are  formed  from  the  cellular  ; 
as,  the  Se'rouS)  Der'moid,  Fi'brous,  and  several  others. 

33.  The  SEROUS  TISSUE   lines  all  the  closed,  or  sac-like 
cavities  of  the  body ;  as,  the  chest,  joints,  and  abdomen.     It 
not  only  lines  these  cavities,  but  is  reflected,  and  invests  the 
organs  contained  in  them.     The  liver  and  the  lungs  are  thus 
invested.     This  membrane  is  of  a  whitish  color,  and  smooth 
on  its  free  surfaces.     These  surfaces  are  kept  moist,  and  pre- 
vented from  adhering  by  a  se*rous  fluid,  which  is  separated 
from  the  blood.     The  use  of  this  membrane   is  to  separate 
organs,  and  also  to  facilitate  the  movement  of  one  part  upon 
another,  by  means  of  its  moist,  polished  surfaces. 

34.  The  DERMOID  TISSUE  covert  the  outside  of  the  body. 

Give  observation  2d.  31.  What  is  said  of  the  identity  of  this  tissue  ? 
32.  Name  the  varieties  of  tissue  formed  from  the  cellular.  33.  Where  is 
the  serous  tissue  found  ?  What  two  offices  does  it  perform  ?  Give  its 
Btructure  What  is  the  use  of  this  membrane  ? 


STKUJTURE    OF    MAN.  21 

It  is  called  the  cu'tis,  (skin.)  This  membrane  is  continuous 
with  the  mucous  at  the  various  orifices  of  the  body,  and  in 
these  situations,  from  the  similarity  of  their  structure,  it  is 
difficult  to  distinguish  between  them. 

Observations.  1st.  In  consequence  of  the  continuity  and 
similarity  of  structure,  there  is  close  sympathy  between  the 
mucous  and  dermoid  membranes.  If  the  functions  of  the 
skin  are  disturbed,  as  by  a  chill,  it  will  frequently  cause  a 
catarrh,  (cold,)  or  diarrhoea.  Again,  in  consequence  of  this 
intimate  sympathy,  these  complaints  can  be  relieved  by  ex- 
citing a  free  action  in  the  vessels  of  the  skin. 

2d.  It  is  no  uncommon  occurrence  that  diseased  or  irri- 
tated conditions  of  the  mucous  membrane  of  the  stomach  or 
intestines  produce  diseases  or  irritations  of  the  skin,  as  is  seen 
in  the  rashes  attendant  on  dyspepsia,  and  eating  certain  spe- 
cies of  fish.  These  eruptions  of  the  skin  can  be  relieved  by 
removing  the  diseased  condition  of  the  stomach. 

35.  The  FIBROUS  TISSUE  consists  of  longitudinal,  parallel 
fibres,  which  are  closely  united.     These  fibres,  in  some  situ- 
ations, form  a  thin,  dense,  strorv  -    nembrane,  like  that  which 
lines  the  internal  surface  of  the  .&  .Jl,  or  invests  the  external 
surface  of  the  bones.     In  other  instances,  they  form  strong, 
inelastic  bands,  called  lig' ..-. -ments,  which  bind  one   bone  tc 
another.     This  tissue  also    jrms  ten'dons,  (white  cords,)  by 
which  the  muscles  are  attached  f       ^  bones. 

Observation.  In  the  disease  cal  -.  rheumatism,  the  fibrous 
tissue  is  the  part  principally  affected  ;  hence  the  joints,  where 
this  tissue  is  most  abundant,  suffer  most  from  this  affection. 

36.  The  ADIPOSE  TISSUE  is  so  arranged  as  to  form  distinct 
bags,  or  cells.     These  contain  a  substance  called  fat.     This 

34  Describe  the  dermoid  tissue.  What  is  said  of  the  sympathy  between 
the  functions  of  the  skin  and  mucous  membrane  ?  Give  another  instance 
of  the  sympathy  between  these  membranes.  35.  Of  what  does  the  fibrou* 
tissue  consist  ?  How  do  these  appear  in  some  situations  ?  How  in  others  ? 
What  tissue  is  generally  affected  in  rheumatism  ? 


22 


ANATOMY,    PHYSIOLOGY,    AND   HYGIENE. 


tissue  is  principally  found  beneath  the  skin,  abdominal  mus- 
cles, and  around  the  heart  and  kidneys ;  while  none  is  found 
in  the  brain,  eye,  ear,  nose,  and  several  other  organs. 

Observation.  In  those  individuals  who  are  corpulent,  there 
is  in  many  instances,  a  great  deposit  of  this  substance.  This 
tissue  accumulates  more  readily  than  others  when  a  person 
becomes  gross,  and  is  earliest  removed  when  the  system 
emaciates,  in  acute  or  chronic  diseases.  Some  of  the  masses 
become,  in  some  instances,  enlarged.  These  enlargements 
are  called  adipose,  or  fatty  tumors. 

Fig.  4. 


Pig.  4.  1,  A  portion  of  the  adipose  tissue.  2,  9,  S,  Minute  bags  containing  fat  3, 
A  cluster  of  these  bags,  separated  and  suspended. 

37.  The  CARTILAGINOUS  TISSUE  is  firm,  smooth,  and  highly 
elastic.  Except  bone,  it  is  the  hardest  part  of  the  animal 
frame.  It  tips  the  ends  of  the  bones  that  concur  in  forming 
a  joint.  Its  use  is  to  facilitate  the  motion  of  the  joints  by  its 
smooth  surface,  while  its  elastic  character  diminishes  the 
shock  that  would  otherwise  be  experienced  if  this  tissue  were 
inelastic. 

36.  Describe  the  adipose  tissue.  Where  does  this  tissue  principally 
exist  ?  Give  observation  in  regard  to  the  adipose  tissue.  37.  Describe  the 
cartilaginous  tissue.  What  is  its  use  ? 


STRUCTURE    OF    MAN. 

38  The  OSSEOUS  TISSUE,  in  composition  and  arrangement 
of  matter,  varies  at  different  periods  of  life,  and  in  different 
bones.  In  some  instances,  the  bony  matter  is  disposed  in 
plates,  while  in  other  instances,  the  arrangement  is  cylindrical. 
Sometimes,  the  bony  matter  is  dense  and  compact ;  again,  it  is 
spongy,  or  porous.  In  the  centre  of  the  long  bones,  a  space 
is  left  which  is  filled  with  a  fatty  substance,  called  mar'row. 

Observation.  Various  opinions  exist  among  physiologists  in 
legard  to  the  use  of  marrow.  Some  suppose  it  serves  as  a 
reservoir  of  nourishment,  while  others,  that  it  keeps  the  bones 
from  becoming  dry  and  brittle.  The  latter  opinion,  however, 
has  been  called  in  question,  as  the  bones  of  the  aged  man 
contain  more  marrow  than  those  of  the  child,  and  they  are 
likewise  more  brittle. 

Fig.  5. 


Fig  5.  A  section  of  the  femur,  (thigh-bone.)  1,  1,  The  extremities,  showing  a 
thin  plate  of  compact  texture,  which  covers  small  cells,  that  diminish  in  size,  but 
increase  in  number,  as  they  approach  the  articulation.  2,  2,  The  walls  of  the  shaft, 
which  are  very  firm  and  solid.  3,  The  cavity  that  contains  the  marrow. 

39.  The  MUSCULAR  TISSUE  is  composed  of  many  fibres, 
hat  unite  to  form  fasciculi,  each  of  which  is  enclosed  in  a 
delicate  layer  of  cellular  tissue.  Bundles  of  these  fasciculi 
constitute  a  muscle. 

Observation.  A  piece  of  boiled  beef  will  clearly  illustrate 
the  arrangement  of  muscular  fibre. 

38.  What  is  said  of  the  osseous  tissue  ?  How  is  the  bony  matter  arranged 
in  different  parts  of  the  animal  frame  ?  What  is  said  of  the  use  of  marrow^ 
89  Of  what  is  the  muscular  tissue  composed  7  How  may  the  arrangemen 
of  muscular  fibre  be  illustrated  7 


24  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

40.  The  MUCOUS    TISSUE    differs    from  the  serous  by  its 
lining  all  the  cavities  which  communicate  with  the  air.     The 
nostrils,  the  mouth,  and  the  stomach  afford  examples.     The 
external  surface  of  this  membrane,  or  that  which  is  exposed 
to  the  air,  is  soft,  and  bears  some  resemblance  to  the  downy 
rind  of  a  peach.     It  is  covered  by  a  viscid  fluid  called  mu'cus. 
This  is  secreted  by  small  gland-cells,  called  ep-i-the'li-a,  or 
secretory  cells  of  the  mucous  membrane.     The  use  of  this 
membrane  and  its  secreted  mucus  is  to  protect  the  inner  sur- 
face of  the  cavities  which  it  lines. 

Observation.  A  remarkable  sympathy  exists  between  the 
remote  parts  of  the  mucous  membrane.  Thus  the  condition 
of  the  stomach  may  be  ascertained  by  an  examination  of  the 
tongue. 

41.  The  NERVOUS  TISSUE  consists  of  soft,  pulpy  matter, 
enclosed  in  a  sheath,  called  neu-ri-lem1  a.     This  tissue  consists 
of  two  substances.     The  one,  of  a  pulpy  character  and  gray 
color,  is  called  cin-e-ri'tious,  (ash-colored.)     The  other,  of  a 
fibrous  character  and  white,  is  named  med'ul-la-ry,  (marrow- 
like.)     In  every  part  of  the  nervous  system  both  substances 
are  united,  with  the  exception  of  the  nervous  fibres  and  fila- 
ments, which  are  solely  composed  of  the  medullary  mattei 
enclosed  in  a  delicate  sheath. 


40.  How  does  tfce  mucous  differ  from  the  serious  tissue  ?  What  is 
the  appearance  of  the  external  surface  of  thia  membrane  ?  Where  is  the 
mucus  secreted  ?  What  is  the  use  of  this  membrane  ?  41.  Of  what  does  th«> 
nervous  tissue  consist?  Describe  the  two  substances  that  enter  into  the 
composition  of  the  nervous  tissue. 


CHEMISTRY    OF    THE    HUMAN    BUJDi*.  25 

CHAPTER     III 

CHEMISTRY  OF  THE  HUMAN  BODY. 

42.  An  ULTIMATE  ELEMENT  is  the  simplest  form  of  matter 
with  which  we  are  acquainted  ;  as  gold,  iron,  &c. 

43.  These     elements     are     divided    into    metallic    and 
non-metallic   substances.      The  metallic   substances  are  Po- 
tas'si-um,   So'di-um,    Cal'ci-um,    Mag-ne'si-um,   A-lu'min-um, 
Iron,  Man'ga-nese,  and    Cop'per.      The    non-metallic   sub 
stances  are  Ox'y-gen,  Hy'dro-gen,  Car'bon,  Ni'tro-gen,  Si-li'- 
ci-um,  Phos'phor-us,  Sulphur,  Chlo'rine,  and  a  few  others. 

44.  POTASH  (potassium    united  with  oxygen)   is  found  in 
the  blood,  bile,  perspiration,  milk,  &c. 

45.  SODA  (sodium  combined  with  oxygen)   exists  in  the 
muscles,  and  in  the  same  fluids  in  which  potash  is  found. 

46.  LIME  (calcium  combined  with  oxygen)  forms  the  prin- 
cipal ingredient  of  the  bones.     The  lime  in  them  is  combined 
with  phosphoric  and  carbonic  acid. 

47.  MAGNESIA  (magnesium  combined  with   oxygen)  exists 
in  the  bones,  brain,  and  in  some  of  the  animal  fluids ;  as  milk. 

48.  SILEX  (silicium  combined  with  oxygen)  is  contained  in 
the  hair  and  in  some  of  the  secretions. 

49.  IRON  forms  the  coloring  principle  of  the  red  globules 
of  the  blood,  and  is  found  in  every  part  of  the  system. 

Observation.  As  metallic  or  mineral  substances  enter  into 
the  ultimate  elements  of  the  body,  the  assertion  that  all  min- 
erals are  poisonous,  however  small  the  quantity,  is  untrue. 

42.  What  is  an  ultimate  element?  Give  examples.  43.  How  are  they 
divided?  Name  the  metallic  substances.  Name  the  non-metallic  substances. 
44.  What  is  said  of  potash  ?  45.  Of  soda?  46.  Oflime  ?  47.  Of  magnesia  ? 
48.  Of  silex?  49.  What  forms  the  coloring  principle  of  the  blood?  What 
it>  said  of  mineral  sabstanres  ? 

3 


26  ANATOMY,    PHYSIOLOGY,   AND   FYGIENE. 

50.  OXYGEN  is  contained  in  all  the  fluids  and  solids  of  the 
body.     It  is  almost  entirely  derived  from  the  inspired  air  and 
water.     It  is  expelled  in  the  form  of  carbonic  acid  and  water 
from  the  lungs  and  skin.     It  is  likewise  removed  in  the  other 
secretions. 

51.  HYDROGEN  is  found  in  all  the  fluids  and  in  all  the  solids 
of  the  body.     It  is  derived  from  the  food,  as  well  as  from 
water  and  other  drinks.     It  exists  in  the  greatest  abundance  in 
the  impure,  dark-colored  blood  of  the  system.     It  is  removed 
by  the  agency  of  the  kidneys,  skin,  lungs,  and  other  excretory 
organs. 

52.  CARBON   is  an  element  in  the  oil,  fat,  albumen,  fibrin, 
gelatin,  bile,  and  mucus.     This  element  likewise  exists  in  the 
impure  blood  in  the   form  of  carbonic  acid  gas.     Carbon  is 
obtained  from  the   food,  and  discharged  from  the  system  by 
the  secretions  and  respiration. 

53.  NITROGEN   is  contained  in  most  animal  matter,  but  is 
most  abundant  in  fibrin.     It  is  not  contained  in  fat  and  a  few 
other  substances. 

Observation.  The  peculiar  smell  of  animal  matter  when 
burning  is  owing  to  nitrogen.  This  element  combined  with 
hydrogen  forms  am-mo'ni-a^  (hartshorn,)  when  animal  matter 
is  in  a  state  of  putrefaction. 

54.  PHOSPHORUS  is  contained  in  many  parts  of  the  system, 
but  more  particularly  in  the  bones.     It  is  generally  found  in 
combination   with   oxygen,    forming  phosphoric   acid.     The 
phosphoric  acid  is  usually  combined  with  alkaline  bases ;  as 
lime  in  the  bones,  forming  phosphate  of  lime. 

55.  SULPHUR  exists  in  the  bones,  muscles,  hair,  and  nails. 
It  is  expelled  from  the  system  by  the  skin  and  intestines. 

56.  CHLORINE   is  found   in  the  blood,  gastric  juice,  milk, 
perspiration,  and  saliva. 

60.  What  is  said  of  oxygen  ?  51.  Of  hydrogen  ?  52.  What  is  saui  ni'  car- 
bon ?  53.  Of  nitrogen  1  How  is  ammonia  formed  1  54.  What  is  said  oj 
phosphorus?  55.  What  is  said  of  sulphur  1  56.  Of  chlorine  » 


CHLMISTRY    OF    THE    HUMAN    BODY.  xJ7 

57.  PROXIMATE  ELEMENTS  are  forms  of  matter  that  exist 
«i  organized  bodies  in  abundance,  and  are  composed  chiefly 
of  oxygen,  hydrogen,  carbon,  and  nitrogen,  arranged  in  dif- 
ferent proportions.     They  exist  already  formed,  and  may  be 
separated  in  many  instances,  by  heat  or  mechanical  means. 
The    most    important    compounds    are    Al-bu'men,    Fi'brin 
Gel'a-tin,  Mu'cus,  Fat,   Ca'se-ine,   Chon'drine,  Lac' tic  acid, 
and  Os'ma-zome. 

58.  ALBUMEN  is  found  in  the  body,  both  in  a  fluid  and  solid 
form.     It  is  an  element  of  the  skin,  glands,  hair,  and  nails, 
and  forms  the  principal  ingredient  of  the  brain.     Albumen  is 
without  color,  taste,  or  smell,  and  it  coagulates  by  heat,  acids, 
and  alcohol. 

Observation.  The  white  of  an  egg  is  composed  of  albu- 
men, which  can  be  coagulated  or  hardened  by  alcohol.  As 
albumen  enters  so  largely  into  the  composition  of  the  brain,  is 
not  the  impaired  intellect  and  moral  degradation  of  the  inebri- 
ate attributable  to  the  effect  of  alcohol  in  hardening  the  albu- 
men of  this  organ  ? 

59.  FIBRIN    exists    abundantly  in   the    blood,  chyle,  and 
lymph.     It  constitutes  the  basis   of  the  muscles.     Fibrin  is 
of  a  .whitish  color,  inodorous,  and  insoluble  in  cold  water.     It 
differs  from  albumen  by  possessing  the  property  of  coagu- 
lating at  all  temperatures. 

Observation.  Fibrin  may  be  obtained  by  washing  the  thick 
part  of  blood  with  cold  water ;  by  this  process,  the  red  glob- 
ules, or  coloring  matter,  are  separated  from  this  element. 

60.  GELATIN  is  found  in  nearly  all  the  solids,  but  it  is  not 
known  to  exist  in  any  of  the  fluids.     It  forms  the  basis  of  the 
cellular  tissue,  and  exists  largely  in  the  skin,  bones,  ligaments, 
and  cartilages. 

57.  What  are  proximate  elements  ?  Do  they  exist  already  formed  in  organ 
ized  bodies  ?  Name  the  most  important  compounds.  58.  What  is  said  of 
albumen?  Give  observation  relative  to  this  element.  59.  Of  fibrin  ?  How 
does  albumen  differ  from  fibrin  ?  How  can  fibrin  be  obtained  ?  60.  \Vhui  at 

6aiJ  ol'  gelatin  / 


28  ANATOMY,    PHYSIOLOGY,  AND    HYGIENE. 

Observation.  Gelatin  is  known  from  other  organic  principles 
by  its  dissolvirig  in  warm  water,  and  forming  "  jelly."  When 
dry,  it  forms  the  hard,  brittle  substance,  called  glue.  Isin- 
glass, which  is  used  m  the  various  mechanical  arts,  is  obtained 
from  the  sounds  of  the  sturgeon. 

61.  Mucus  is  a  viscid  fluid  secreted  by  the  gland-cells,  or 
epithelia.     Various  substances  are  included  under  the  name 
of  mucus.     It   is  generally  alkaline,    but  its  true  chemical 
character  is  imperfectly  understood.     It  serves  to  moisten  and 
defend  the  mucous  membrane.     It  is  found  in  the  cuticle, 
brain,  and  nails  ;  and  is  scarcely  soluble  in  water,  especially 
when  dry.     (Appendix  C.) 

62.  OSMAZOME  is  a  substance  of  an  aromatic  flavor.     It  is 
of   a   yellowish-brown   color,  and  is  soluble    both  in  water 
and  alcohol,  but    does    not    form    a   jelly  by  concentration. 
It  is  found  in   all  the  fluids,  and  in  some  of  the  solids ;  as 
the  brain. 

Observation.  The  characteristic  odor  and  taste  of  soup  are 
owing  to  osmazome. 

63.  There  are  several  acids  found   in  the  human  system  ; 
as  the  A-ce'tic,  Ben-zo'ic,  Ox-al'ic,  U'ric,  and  some  other  sub- 
stances, but  not  of  sufficient  importance  to  require  a  particu- 
lar description. 

How  is  it  'known  from  other  organic  principles?  61.  What  is  said  of 
mucus  ?  62.  Of  osmazoine  ?  To  what  are  the  taste  and  odor  of  toup 
•wing  r  63.  What  acids  are  found  in  the  system  ? 


ANATOMY    OF    THE 


CHAPTER 

THE    BONES. 

64.  THE  bones  are  firm  and  hard,  and  tf  a  dull  whiie 
color.     In  all  the  higher  orders  of  animals,  among  which  is 
man,  they  are  in  the  interior  of  the  body,  while  m  lobsters, 
crabs,  &c.,  they  are  on  the  outside,  forming  a  case  which 
protects  the  more  delicate  parts  from  injury. 

65.  In  the  mechanism  of  man,  the  variety  of  movements 
he   is  called  to  perform   requires  a  correspondent  variety  of 
component  parts,  and  the  different  bones  of  the  system  are 
so  admirably  adapted  to  each  other,  that  they  admit  of  nu- 
merous and  varied  motions. 

66.  When  the  bones  composing  the  skeleton  are  united  by 
natural  ligaments,  they  form  what  is  called  a  natural  skeleton  , 
when  united  by  wires,  what  is  termed  an  artificial  skeleton. 

67.  The    elevations,  or   protuberances,  of  the    bones  are 
called  proc'es-ses,  and   are,  generally,  the  points  of  attach- 
ment for  the  muscles  and  ligaments. 


ANATOMY  OF  THE  BONES. 

68.  The  BONES  are  composed  of  both  animal  and  earthy 
matter.  The  earthy  portion  of  the  bones  gives  them  solidity 
and  strength,  while  the  animal  part  endows  them  with  vitality 

64.  What  is  said  of  the  bones  ?  65.  Is  there  an  adaptation  of  the  bones 
of  the  system  to  the  offices  they  are  required  to  perform  ?  66.  What  is  a 
natural  skeleton  ?  What  an  artificial  ?  67.  What  part  of  the  bones  are 
called  processes  ?  68 — 73.  Give  the  structure  of  the  bones.  68.  Of  what  are 
the  bones  composed  ?  What  are  the  different  uses  of  the  component  parts 
of  the  bones  ? 

%  * 


30  ANATOMY,    PHYSIOLOGY,    AF^    HYGIENE. 

Experiments.     1st.   To  show  tte  earthy  without  the  animal 
matter,  burn  a  bone  in  a  clear  fire  for  about  fifteen  minutes, 
and  it  becomes  white  and  Kittle,  because  the  gelatin,  or  ani 
mal  matter  of  the  bone,  fcas  been  destroyed. 

2d.  To  show  the  animal  without  the  earthy  matter  of  the 
br,;ies,  immerse  a  slender  bone  for  a  few  days  in  a  weak  acid, 
( Due  part  muriatic  acid  and  six  parts  water,)  and  it  can  then 
be  bent  in  an/  direction.  In  this  experiment,  the  acid  has 
removed  the  earthy  matter,  (carbonate  and  phosphate  of  lime,) 
yet  the  form  of  the  bone  is  unchanged. 

69.  The  bones  are  formed  from  the  blood,  and  are  sub- 
jected to  several  changes  before  they  are  perfected.     At  their 
early  formative  stage,  they  are  cartilaginous.     The  vessels  of 
the  cartilage,  at.  this  period,  convey  only  the  lymph,  or  white 
portion  of  the  blood  ;  subsequently,   they  convey  red   blood. 
At  this  time,  true  ossification  (the  deposition  of  phosphate  and 
carbonate  of  lime)  commences  at  certain  points,  which  are 
called  the  points  of  ossification. 

70.  Most  of  the   bones  are  formed   of  several   pieces,  or 
centres  of  ossification.     This  is  seen  in  the  long  bones  which 
have   their  extremities  separated  from   the   body  by  a   thin 
partition  of  cartilage.     It  is  some  time  before  these  separate 
pieces  are  united  to  form  one  bone. 

71.  When  the  process  of  ossification  is  completed,  there 
is   still  a  constant  change  in  the  bones.     They  increase  in 
bulk,  and   become  less  vascular,  until  middle   age.     In  ad- 
vanced  life,  the  elevations  upon  their  surface  and  near  the 
extremities   become  more  prominent,  particularly  in  individ- 
uals accustomed   to  labor.     As  a  person  advances  in  years, 
the  vitality  diminishes,  and   in  extreme  old  age,  the  earthy 

How  can  the  earthy  matter  of  the  bones  be  shown  ?  The  animal  ? 
89.  What  is  the  appearance  of  the  bones  in  their  early  formative  stage  ? 
When  does  true  ossification  commence  ?  70.  How  are  most  of  the  bones 
formed  ?  71.  What  is  said  of  the  various  changes  of  the  bones  after 
ossification  ? 


UJt    THE    BONES.  3l 

substance    predominates ;    consequently,  the    bones   are   ex 
trernely  brittle. 

72.  The  fibrous  membrane  that  invests  the  bones  is  caJ  .ed 
per-i-os'te-um ;  that  which  covers  the  cartilages  is  c/.lled 
per-i-ckoridri-um.  When  this  membrarrj  invests  the  skull, 
it  is  called  per-i-cra'ni-um. 

Fig.  6. 


Fig.  G.  A  section  rf  the  knee-joint.  The  lower  part  of  the  femur,  (thigh-bone,, 
and  upper  part  of  the  tibia,  (leg-bone,)  are  seen  ossified  at  1,  1.  The  cartilaginous 
extremities  of  the  two  bones  are  seen  at  d,  d.  The  points  of  ossification  of  the 
extremities,  are  seen  at  2,  2.  The  patella,  or  knee-pan,  is  seen  at  t.  5,  A  point, 
or  centre  of  ossification. 

73.   The  PERIOSTEUM  is  a  firm   membrane  immediately  in 
vesting  the  bones,  except  where  they  are  tipped  with  cartilage, 
and  the  crowns  of  the  teeth,  which  are  protected  by  enamel. 
This  membrane  has  minute  nerves,  and  when  healthy,  pos- 

72.  What  is  the  membrane  called  that  invests  the  bones  ?  That  covers 
the  cartilage  ?  That  invests  the  skull  ?  Explain  fig.  6.  73.  Describe  the 
periosteum. 


d^  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

sesses  but  little  sensibility.  It  is  tbe  nutrient  membrane  of 
the  bone,  endowing  its  exterior  with  vitality ;  it  also  gives 
nsertion  to  the  tendons  and  connecting  ligaments  of  the 
joints. 

74.  There  are  two  hundred  and  eight*  bones  in  the  human 
body,  beside  the  teeth.     These,  for  convenience,  are  divided 
into  four  parts  :   1st.  The  bones  of  the  Head.     2d.    The  bones 
of  the    Trunk.     3d.   The  bones  of  the    Upper   Extremities 
4th.   The  bones  of  the  Lower  Extremities. 

75.  The  bones  of  the  HEAD  are  divided  into  those  of  the 
Skull,  Ear,  and  Face. 

76.  The    SKULL  is  composed  of  eight  bones.     They  are 
formed  of  two  plates,  or  tablets  of  bony  matter,  united  by  a 
porous  portion  of  bone.     The  external  tablet  is  fibrous  and 
tough  ;  the  internal   plate    is   dense  and  hard,  and  is  called 
the  vit're-oiLs,  or   glassy   table.      These   tough,  hard    plates 
are  adapted   to   resist   the  penetration  of  sharp  instruments, 
while  the  different  degrees  of  density  possessed  by  the  two 
tablets,  and  the   intervening  spongy  bone,  serve  to  diminish 
the  vibrations  that  would  occur  in  falls  or  blows. 

77.  The  skull  is  convex  externally,  and  at  the  base  much 
thicker  than  at  the  top  or  sides.     The  most  important  part  of 
the  brain  is  placed  here,  completely  out  of  the  way  of  injury, 
unless  of  a  very  serious  nature.     The   base  of  the  cranium, 
or  skull,  has  many  projections,  depressions,  and  apertures ; 
the   latter   affording    passages    for    the    nerves    and    blood- 
vessels. 


*  Some  anatomises  reckon  'more  than  this  number,  others  less,  foi 
the  reason  that,  at  different  periods  of  life,  the  number  of  pieces  of 
which  one  bone  is  formed,  varies.  Example.  The  breast-bone,  in 
infancy,  has  eight  pieces ;  in  youth,  three ;  in  old  age,  but  one. 

74.  How  many  bones  in  the  human  body  ?  How  are  they  divided » 
75 — 81.  Give  the  anatomy  of  the  bones  of  the  head.  7-5.  How  are  the  bonea 
of  the  head  divided  ?  76.  Describe  the  bones  of  the  skull.  77.  "Whal 
is  the  form  i>f  the  skull  ?  What  does  the  base  of  the  skull  present  ? 


ANATOMY    OF    THE    BONES.  *5.3 

78.  The  bones  of  the  cranium  are  united  by  ragged 
edges,  called  sut'ures.  The  edges  of  each  bone  interlock 
with  each  other,  producing  a  union,  styled,  in  carpentry,  dove- 
tailing. They  interrupt,  in  a  measure,  the  vibrations  pro- 
duced by  external  blows,  and  also  prevent  fractures  from 
extending  as  far  as  they  otherwise  would,  in  one  continued 
bone.  From  infancy  to  the  twelfth  year,  the  sutures  are 
imperfect ;  but,  from  that  time  to  thirty-five  or  forty,  they  are 
distinctly  marked ;  in  old  age,  they  are  nearly  obliterated. 

Fig.  7. 


Fig.  7  I,  1,  The  coronal  suture  at  the  front  and  upper  part  of  the  skull,  or  era 
nium.  2,  The  sagittal  suture  on  the  top  of  the  skull.  3,  3,  The  lambdoidal  suture 
at  the  back  part  of  the  cranium. 

79.  We  find  as  great  a  diversity  in  the  form  and  texture 
of  the  skull-bone,  as  in  the  expression  of  the  face.  The  head 
of  the  New  Hollander  is  small;  thai  of  the  African  is  com- 
pressed ;  while  the  Caucasian  is  distinguished  for  the  beautiful 
oval  form  of  the  head.  The  Greek  skulls,  'in  texture,  are 
close  and  fine,  while  the  Swiss  are  softer  and  more  open. 

78.  How  are  the  bones  of  the  skull  united  ?  What  are  the  uses  of  the 
sutures  ?  Mention  the  appearance  of  the  sutures  at  different  ages.  What 
does  fig.  7  represent?  79.  What  is  said  respecting  the  form  and  texture 
of  the  skull  in  different  nations  ? 


31  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE, 

80.  In  each  EAR  are  four  very  small  bones.     They  aid  in 
hearing. 

81.  In  the  FACE  are  fourteen  bones,  some  of  which  serve 
for  the  attachment  of  powerful   muscles,  which  are  more  or 
less  called  into  action  in   masticating  food ;  others  retain  m 
place  the  soft  parts  of  the  face. 

Fig.  8. 


Fig.  8.  1,  The  frontal,  or  bone  of  the  forehead.  2.  The  parietal  bone.  3,  Tho 
temporal  bone.  4,  The  zygomatic  process  of  the  temporal  bone.  5,  The  malur 
(cheek)  bone.  6,  The  superior  maxillary  bone,  (upper  jaw.)  7,  The  vomer,  that 
separates  *?he  cavities  of  the  nose.  8,  The  inferior  maxillary  bone,  (lower  jaw.) 
9.  The  cavity  for  the  eye. 

82.  The  TRUNK  has  fifty-four  bones  —  twenty-four  Ribs ; 
twenty-four  bones  in  the  Spi'nal  Column,  (back-bone  ;)  four 
in  the  Pelvis ;  the  Ster'num,  (breast-bone  ;)  and  the  Os  hy- 
md'es,  (.the  bone  at  the  base  of  the  tongue.)  They  are  so 
arranged"  as  to  form,  with  the  soft  parts  attached  to  them,  two 
cavities,  called  the  Tho'rax  (chest)  and  Ab-do'men. 

80.  How  many  bones  in  the  ear  ?  81.  How  many  bones  in  the  face  ? 
What  is  their  use  ?  Explain  fig.  8.  82 — 94.  Give  the  anatomy  of  the  bones 
9f  the  trunk,  82.  How  many  bones  in  the  trunk  ?  Name  them.  What 
do  they  form  by  their  arrangement  ? 


ANATOMY    OF    THE    BONES.  35 

83.  The  THORAX  is  formed  by  the  sternum,  in  front;  the 
ribs,  at  the  sides ;  and  the  twelve  dorsal  bones  of  the  spinal 
column,  posteriorly.  The  natural  form  of  the  chest  is  a  cone, 
with  its  apex  above  ;  but  fashion,  in  many  instances,  has  near- 
ly inverted  this  order.  This  cavity  contains  the  lungs,  heart, 
and  large  blood-vessels. 

Fig.  9. 


Fig  9.  1,  The  first  bone  of  the  sternum,  (breast-bone.x  2.  The  second  bone-df  the 
eternum.  3,  The  cartilage  of  the  sternum.  4,  The  first  dorsal  vertebra,  (a  bone  of 
the  spinal  column.)  5,  The  last  dorsal  vertebra.  6,  The  first  rib.  7,  Its  head. 
8,  Its  neck.  9,  Its  tubercle.  10,  The  seventh,  or  last  true  rib.  11,  The  cartilage 
of  the  third  rib.  12,  The  floating  ribs. 

84.  The  STERNUM  is  composed  of  eight  pieces  in  the  child. 
These  unite  and  form  but  three  parts  in  the  adult.     In  youth, 
the  two  uppei    portions  are  converted  into  bone,  while  the 
lower  portion  remains  cartilaginous  and  flexible  until  extreme 
old  age,  when  it  is  often  converted  into  bone. 

85.  The  RIBS  are  connected  with  the  spinal  column,  and  in- 
crease in  length  as  far  as  the  seventh.     From  this  they  succes- 

83.  Describe  the  thorax.    Explair  fig.  9.     84.  Describe  the   sternum 
85.  Describe  tke  ribs. 


36  ANATOMY,    PHYSIOLOGY,    AND    HYGiENE. 

sively  become  shorter.  The  direction  of  the  ribs  from  above, 
downward,  is  oblique,  and  their  curve  diminishes  from  the  first 
to  the  twelfth.  The  external  surface  of  each  rib  is  convex  ;  the 
internal,  concave.  The  inferior,  or  lower  ribs,  are,  however, 
very  flat. 

86.  The    seven    upper   ribs   are   united    to    the    sternum, 
through  the  medium  of  cartilages,  and  are  called  the  true  ribs. 
The  cartilages  of  the  next  three  are  united  with  each  other, 
and  are  not  attached  to  the  sternum ;  these  are  called  false 
ribs.     The  lowest  two  are  called  floating  ribs,  as  they  are  not 
connected  either  with  the  sternum  or  the  other  ribs. 

87.  The  SPINAL  COLUMN  is  composed  of  twenty-four  pieces 
of  bone.     Each  piece  is  called  a  vert'e-bra.     On  examining 
one  of  the  bones,  we  find  seven  projections,  called  processes ; 
four  of  these,  that  are  employed  in  binding  the  bones  together, 
are  called  articulating  processes ;  two  of  the  remaining  are 
called  the  transverse ;  and  the  other,  the  spinous.     The  last 
three  give  attachment  to  the  muscles  of  the  back. 

88.  The    large  part  of  the  vertebra,  called   the  body,  is 
round  and  spongy  in  its  texture,   like  the  extremity  of  the 
round  bones.     The  processes  are  of  a  more  dense  character. 
The  projections  are  so  arranged  that  a  tube,  or  canal,  is  formed 
immediately  behind  the  bodies  of  the  vertebrae,  in  which  is 
placed    the   me-dul'la    spi-na'lis,    (spinal    cord,)    sometimes 
called  the  pith  of  the  back-bone. 

89.  Between  these  joints,  or  vertebrae,  is  a  peculiar  and 
highly  elastic    substance,  which   much  facilitates  the  bending 
movements  of  the  back.     Th:.s  compressible  cushion  of  car- 
tilage also  serves    the    important    purpose    of  diffusing   and 
diminishing  the  shock  in  walking,  running,  or  leaping,  and 
tends  to  protect  the  delicate  texture  of  the  brain. 

86.  How  are  the  ribs  united  to  the  sternum  ?  87-  Describe  the  spinal 
column.  88.  Give  the  structure  of  the  vertebra.  Where  is  the  spinal 
cord  placed  ?  89.  What  is  placed  between  each  vei  .ebra  What  is 
it.-,  use  ? 


ANATOMY    OF    THE    BONES  3*7 

90.  Another  provision  for  the  protection  of  the  brain, 
which  bears  convincing  proof  of  the  wisdom  and  beneficence 
of  the  Creator,  is  the  antero-posterior,  or  forward  and  back- 
ward curve  of  the  spinal  column.  Were  it  a  straight  column, 
standing  perpendicularly,  the  slightest  jar,  in  walking,  would 
cause  it  to  recoil  with  a  sudden  jerk  ;  because,  the  weight 
bearing  equally,  the  spine  would  neither  yield  to  the  one  side 
nor  the  other.  But,  shaped  as  it  is,  we  find  it  yielding  in  the 
direction  of  the  curves,  and  thus  the  force  of  the  shock  is 
diffused. 

Fig.  10. '  Fig.  11. 


3 

Pig.  10.  A  vertebra  of  the  neck.  1,  The  body  of  the  vertebra.  2,  The  spinal 
canal.  4,  The  spinoiis  process,  cleft  at  its  extremity.  5,  The  transverse  process 
7,  The  inferior  articulating  process.  8,  The  superior  articulating  process. 

Fig.  11.  1,  The  cartilaginous  substance  that  connects  the  bodies  of  the  vertebra;. 
•2,  The  body  of  the  vertebra.  3,  The  spinous  process.  ~4,  4,  The  transverse  pro- 
cesses. 5,  5,  The  articulating  processes.  6,  6,  A  portion  of  the  bony  bridge  that 
assists  in  forming  the  spinal  canal,  (7.) 

Observation.  A  good  idea  of  the  structure  of  the  vertebrae 
may  be  obtained  by  examining  the  spinal  column  of  a 
domestic  animal,  as  the  dog,  cat,  or  pig. 

91.  The   PELVIS  is  composed  of  four  bones ;  the  two  in- 
nom-i-na'ta,  (nameless  bones,)  the  sa'crum,  and  the  coc'cyx. 

92.  The  INNOMINATUM,  in  the  child,  consists  of  three  pieces. 

90.    What  is    said   of   the    curves  of   the  spinal  column  ?    "What  is 
represented  by  fig.  10  ?     By  fig.  11  ?     How  can  the  structure  of  the  vertebne 
foe  seen  ?     91.  Of  how  many  bones  is  the  pelvis  composed  ?     92.   What  is 
said  of  the  innominatmn  in  the  child  ? 
4 


38  ANATOMY,    PHYSIOLOGY,    AND    HYGIJ2NE. 

These,  in  the  adult,  become  united,  and  constitute  but  one 
bone.  In  the  sides  of  these  bones  is  a  deep  socket,  or 
depression,  like  a  cup,  called  the  ac-e-tab'u-lum,  in  which  the 
round  head  of  the  thigh-bone  is  placed. 

93.  The  SACRUM,  so  called  because  the  ancients  offered  it 
in  sacrifices,  is  a  wedge-shaped  bone,  that  is  placed  between 
the  innominata,  and  to  which  it  is  bound  by  ligaments.  Upon 
its  upper  surface  it  connects  with  the  lower  vertebra.  At  its 
inferior,  or  lower  angle,  it  is  united  to  the  coccyx.  It  is 
concave  upon  its  anterior,  and  convex  upon  its  posterior 

surface. 

Fig.  12. 


Pig.  c*.  i,  1,  The  innominata,  (nameless  bones.)  2,  The  sacrum.  3,  The  coccyx 
4,  4,  The  acetabulum.  o,  a,  The  pubic  portion  of  the  innominata.  d,  The  arch  of 
the  pubesj  e,  The  junction  of  the  sacrum  and  lower  lumbar  vertebra. 

94.  The  COCCYX,  in  Infants,  consists  of  several  pieces, 
which,  in  youth,  become  united  and  form  one  bone.  This  is 
the  terminal  extremity  of  the  spinal  column. 

In  the  adult  ?    Describe  the  acetabulum.    93.  Describe  the    sacrur 
Explain  fig.  12.    94.  Describe  the  coccyx. 


ANATOMY    OF    THE    BONES. 

CHAPTER     V. 

ANATOMY    OF    THE    BONES,     CONTINUEl 

95.  THE  bones  of  the  upper  and  lower  limbs  are  enlarge: 
at  each  extremity,  and  have  projections,  or  processes.     To 
these,  the  tendons  of  muscles  and  ligaments  are    attached, 
which  connect  one  bone  with  another.     The  shaft  of  these 
bones  is  cylindrical  and  hollow,  and  in  structure,  their  exterior 
surface  is  hard  and  compact,  while   the   interior  portion  is 
of  a  reticulated  character.     The  enlarged  extremities  of  the 
round  bones  are  more  porous  than  the  main  shaft. 

96.  The  TIPPER  EXTREMITIES  contain   sixty-four   bones  — 
the  Scap'u-la,  (shoulder-blade ;)  the  Clav'i-cle,  (collar-bone  ;) 
the  Hu'mer-us,  (first  bone  of  the  arm  ;)  the  Ul'na  and  Ra'di- 
tts,  (bones  of  the  fore-arm  ;)  the  Car'pus^  (wrist ;)  the  Met-a- 
car'pus,  (palm  of  the  hand  ;)  and   the  Pha-lan'ges,  (fingers 
and  thumb.) 

97.  The  CLAVICLE  is  attached,  at  one  extremity,  to  the 
sternum  ;  at  the  other,  it  is  united  to  the  scapula.     It  is  shaped 
like  the  Italic  f.     Its  use  is  to  keep  the  arms  from  sliding 
toward  the  breast. 

98.  The  SCAPULA  is  situated  upon  the  upper  and  back  part 
of  the  chest.     It  is  flat,  thin,  and  of  a  triangular  form.     This 
bone  lies  upon  and  is  retained  in  its  position  by  muscles.     By 
their  contractions  it  may  be  moved  in  different  directions. 

99.  The  HUMERTTS  is  cylindrical,  and  is  joined  at  the  elbow 
with  the  ulna  of  the  fore-arm  ;  at  the  scapular  extremity,  it  is 

95—104.  Give  the  anatomy  of  the  bones  of  the  upper  extremities.  95.  Give 
the  structure  of  the  bones  of  the  extremities.  96.  How  many  bones  in 
the  upper  extremities  ?  Name  them.  97.  Give  the  attachments  of  the 
clavicle.  What  is  its  use  ?  98.  Describe  the  scapula.  How  is  it  re 
tained  in  its  position?  99.  Describe  the  humerus. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE 

lodged  in  the  glenoid  cavity,  where    it  is  surrounded  by 
membranous  bag,  called  the  capsular  ligament. 


Fig.  13. 


Fig.  14. 


Fig.  13.  1,  The  shaft  of  the  humerus.  2,  The  large,  round  head  that  is  placed  m 
Hie  glenoid  cavity.  3,  4,  Processes,  to  which  muscles  are  attached.  5,  A  process, 
called  the  external  elbow.  6,  A  process,  called  the  internal  elbow.  7,  The  articu- 
lating surface  upon  which  the  ulna  rolls. 

Fig.  14.  1,  The  body  of  the  ulna.  2,  The  shaft  of  the  radius.  3,  The  upper 
articulation  of  the  radius  and  ulna.  4,  Articulating  cavity,  in  which  the  lower 
extremity  of  the  humerus  is  placed.  5,  Upper  extremity  of  the  ulna,  called  the 
olecranon  process,  which  forms  the  point  of  the  elbow.  6,  Space  between  the  radius* 
and  ulna,  filled  by  the  intervening  ligament.  7,  Styloid  process  of  the  ulna.  8,  Sur- 
face of  the  radius  and  the  ulna,  where  they  articulate  with  the  bones  of  the  wrist. 
9,  Styloid  process  of  the  radius. 

100.  The  ULNA  articulates  with  the  humerus  at  the  elbow, 
and  forms  a  perfect  hinge-joint.  This  bone  is  situated  on  the 
inner  side  of  the  fore-arm. 

What  is  represented  by  fig.  1,3?     By  fig.  14?     100.   Describe  the  ulna. 


AISATOMY    OF    THE    BONKS. 


41 


101.  Tlu  RADIUS  articulates  with  the  bones  of  the  carpus 
and  forms  the  wrist-joint.     This  bone  is  situated  on  the  out 
side  of  the  fore-arm,  (the  side  on  which  the  thumb  is  placed.; 
The  ulna  and  radius,  at  their  extremities,  articulate  with  each 
other,  by  which  union  the  hand  is  made  to  rotate,  permitting 
its  complicated  and  varied  movements. 

102.  The  CARPUS   is  composed   of  eight  bones,  ranged  in 
two  rows,  and  so  firmly  bound  together,  as  to  pennit  only  » 
small  amount  of  movement. 


Fig.  15. 


Fig.  16. 


Fig.  15.  u,  The  ulna.  R,  The  radius,  s,  The  scaphoid  bone.  L,  The  semilunar 
bone,  c,  The  cuneiform  bone.  P,  The  pisiform  bone.  ^These  four  form  the  first  row  of 
carpal  bones.  T,  T,  The  trapezium  and  trapezoid  bones.  M,  The  os  magnum,  u,  The 
unciform  bone.  These  four  form  the  second  row  of  carpal  bones.  1,  1,  1,  1,  1,  The 
metacarpal  bones  of  the  thumb  and  fingers. 

Fig.  16.  10,  10,  10,  The  metacarpal  bones  of  the  hand.  11,11,  First  range  of  fin- 
ger-bonea.  12,  12,  Second  range  of  finger-bones.  13,  13,  Third  range  of  finger-bones 
14,  15,  Bones  of  the  thumb. 

103.    The  METACARPUS  is  composed  of  five  bones,  upon  four 
of  which  the  first  range   of  the  finger-bones  is  placed  ;  and 


101.  The  radius.     102.  How  many  bones  in  the  carpus?    How  are  they 
ranged  ?     103    Describe  the  metacarpus 

4* 


42  ANATOMY     PHYSIOLOGY,    AND    HYGIENE. 

upon  the  other,  the  first  bone  of  the  thumh.     The  five  meta 
carpal  bones  articulate  with  the  second  range  of  carpal  bones. 

104.  The    PHALANGES   of  the  fingers   have   three    ranges 
of  bones,  while  the  thumb  has  but  two. 

Observation.  The  wonderful  adaptation  of  the  hand  to  all 
the  mechanical  offices  of  life,  is  one  cause  of  man's  superior- 
ity over  the  rest  of  creation.  This  arises  from  the  size  and 
strength  of  the  thumbs,  and  the  different  lengths  of  the  fingers. 

105.  The  LOWER  EXTREMITIES  contain  sixty  bones  —  the 
Fe'mur,  (thigh-bone ;)  the  Pa-tel'la,  (knee-pan ;)  the  Tib'i-a 
(shin-bone  ;)  the  Fib'u-la,  (small  bone  of  the  leg ;)  the  Tar'sus, 
(instep;)  the  Met-a-tar'sus,  (middle  of  the  foot;)  and  the  Pka- 
lan'ges,  (toes.) 

106.  The  FEMUR  is  the  longest  bone   in  the  system.     It 
supports  the  weight  of  the  head,  trunk,  and  upper  extremities. 
The  large,  round  head  of  this  bone  is  placed  in  the  acetabu- 
lum.     This  articulation  is  a  perfect  specimen  of  the  ball  and 
socket  joint. 

107.  The  PATELLA  is  a  small  bone  connected  with  the  tibia 
by  a  strong  ligament.     The  tendon   of  the  ex-tens'or  muscles 
of  the  leg  is  attached  to  its  upper  edge.     This  bone  is   placed 
on  the  anterior  part  of  the  lower  extremity  of  the  femur,  and 
acts  like  a  pulley,  in  the  extension  of  the  limb. 

108.  The  TIBIA  is  the  largest  bone  of  the  leg.     It  is  of  ti 
triangular  shape,  and  enlarged  at  each  extremity. 

109.  The  FIBULA  is  a  smaller  bone  than  the  tibia,  but  of  sirn 
liar  shape.     It  is  firmly  bound  to  the  tibia,  at  each  extremity. 

110.  The  TARSUS  is  formed  of  seven  irregular  bones,  which 
are  so  firmly  bound  together  as  to  permit  but  little  movement. 


104.  How  many  ranges  of  bones  have  the  phalanges  ?  105 — 112.  Give 
the  anatomy  of  the  bones  of  the  lower  extremities.  105.  How  many  bones 
in  the  lower  extremities  ?  Name  them.  106.  Describe  the  femur. 
107.  Describe  the  patella.  What  is  its  function  ?  108.  What  is  the 
largest  bone  of  the  leg  called  ?  What  is  its  form  ?  109.  What  is  said 
of  the  fibula  ?  110.  Describe  the  tarsus. 


ANATOMY    OF    THE    BONES. 

Fig.  17.  Fig.  18. 


Fig  17.  1,  The  shaft  of  the  femur,  (thigh-bone.)  2,  A  projection,  called  tlw 
trochantar  minor,  to  which  are  attached  some  strong  muscles.  4,  The  trochantar 
major,  to  which  the  large  muscles  of  the  hip  are  attached.  3,  The  head  of  the  fe- 
mur. 5,  The  external  projection  of  the  femur,  called  the  external  condyle.  6,  Tho 
internal  projection,  called  the  internal  condyle.  7,  The  surface  of  the  lower  extrem- 
ity of  the  femur,  that  articulates  with  the  tibia,  and  upon  which  the  patella  slides. 

Fig.  18.  1,  The  tibia.  5,  The 'fibula.  8,  The  space  between  the  two,  filled  with 
the  inter-osseous  ligament.  6,  The  junction  of  the  tibia  and  fibula  at  their  upper 
extremity.  2,  The  external  malleolar  process,  called  the  external  ankle.  3,  The 
internal  malleolar  process,  called  the  internal  ankle.  4,  The  surface  of  the  lower 
extremity  of  the  tibia,  that  unites  with  one  of  the  tarsal  bones  to  form  the  ankle-joint. 
7,  The  upper  extremity  of  the  tibia,  upon  which  the  lower  extremity  of  the  femur 
rests. 


Explain  fig.  17.    Explain  fig.  18. 


44  ANATOMV,    PHYSIOLOGY,    AND    HYGIENE 

111.  The  METATARSAL  bones  are  five  in  number.  The\ 
articulate  at  one  extremity  with  one  range  of  tarsal  bones  ;  a 
the  other  extremity,  with  the  first  range  of  the  toe-bones. 

Fig.  19. 


Fig.  19.  A  representation  of  the  upper  surface  of  the  bones  of  the  foct.  I,  The 
surface  of  the  astragulus,  where  it  unites  with  the  tibia.  2,  The  body  of  the  astrag- 
nliis.  3,  The  calcis,  (heel-bone.)  4,  The  scaphoid  bone.  5,  6,  7,  The  cuneiform 
bines.  8,  The  cuboid.  9,  9,  9,  The  metatarsal  bones.  10,  The  first  bone  of  the  great 
toe.  11,  The  second  bone.  12,  13,  14,  Three  ranges  of  bones,  forming  the  small 


toes 


Fig.  20. 


Fig.  20.  A  side  view  of  the  bones  of  the  foot,  showing  its  arched  form.  The  arc'a 
fsts  upon  the  heel  behind,  and  the  ball  of  the  toes  in  front.  1,  The  ower  part  of  the 
tibia.  2,  3,  4,  5,  Bones  of  the  tarsus.  6,  The  metatarsal  bone.  7,  8,  The  bones  of 
the  great  toe.  These  bones  are  so  united  as  to  secure  a  great  degree  of  elastic  ny,  01 
spring. 

Observation.     The  tarsal  and  metatarsal  bones  are  united 
so  as  to  give  the  foot  an  arched  form,  convex  above,  and  con- 
ill.  Describe  the  metatarsal  bones.     Explain  fig.  19.     What  is  repre- 
sented by  fig.  20  ?     What  is  said  of  the  arrangement  of  the  bones  of  tht 
foot  ? 


ANATOMY    OF    THE    BONES. 


45 


cave  below.  This  structure  conduces  to  the  elasticity  of  the 
step,  and  the  weight  of  the  body  is  transmitted  to  the  ground 
by  the  spring  of  the  arch,  in  a  manner  which  prevents  injury 
to  the  numerous  organs. 

112.  The  PHALANGES  (fig.  19)  are  composed  of  fourteen 
bones ;  each  of  the  small   toes  has  three  ranges  of  bones, 
while  the  great  toe  has  but  two. 

113.  The  JOINTS  form  an  interesting  part  of  the  body.     In 
their  construction,  every  thing  shows  the  regard  that  has  been 
paid  to  the  security  and  the  facility  of  motion  of  the  parts  thus 
connected  together.     They  are  composed  of  the  extremi\ies 
of  two  or  more    bones,   Car'ti-lages*    (gristles,)    Syn-o'vi  al 
membrane,  and  Lig'a-ments. 


Fig.  22. 


Fig.  21  The  relative  position  of  the  bones,  cartilages,  and  synovial  membrane 
I,  1,  The  extremities  of  two  bones  that  concur  to  form  a  joint.  2,  2,  The  carti- 
lages that  cover  the  end  of  the  bones.  3,  3,  3,  3,  The  synovial  membrane  which 
ct  vers  the  cartilage  of  both  bones,  and  is  then  doubled  back  from  one  to  the  othei ; 
it  is  represented  by  the  dotted  lines. 

Fig.  22.  A  vertical  section  of  the  knee-joint.  1,  The  femur.  3,  The  patella. 
5,  The  tibia.  2,  4,  The  ligaments  of  the  patella.  6,  The  cartilage  of  the  tibia 
12,  The  cartilage  of  the  femur.  *  *  *  *,  The  synovial  membrane. 

114.    CARTILAGE  is  a  smooth,  solid,  elastic  substance,  of  a 
pearly  whiteness,  softer  than  bone.     It  forms  upon  the  articu- 

112.  Describe  the  phalanges.  113 — 118.  Give  the  anatomy  of  the  joints 
113.  What  is  said  of  the  joints  ?  Of  what  are  the  joints  composed 
What  is  illustrated  by  fig.  21?  By  fig.  22?  114.  Define  cartilage. 


16 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


lar  surfaces  of  the  bones  a  thin  incrustation,  not  more  than 
the  sixteenth  of  an  inch  in  thickness.  Upon  convex  surfaces 
it  is  the  thickest  in  the  centre,  and  thin  toward  the  circum- 
ference ;  while  upon  concave  surfaces,  an  opposite  arrange- 
ment is  presented. 

115.  The  SYNOVIAL  MEMBRANE  is  a  thin,  membranous 
layer,  which  covers  the  cartilages,  and  is  thence  bent  back, 
or  reflected  upon  the  inner  surfaces  of  the  ligaments  which 
surround  and  enter  into  the  composition  of  the  joints.  This 
membrane  forms  a  closed  sac,  like  the  membrane  that  lines 

an  egg-shell. 

Fig.  23.  Fig.  24. 


Fig.  23.  The  anterior  ligaments  of  the  knee-joint.  1,  The  tendon  of  the  m:?s«le 
that  extends  the  leg.  2,  The  patella.  3,  The  anterior  ligament  of  the  patella,  neat 
its  insertion.  4,  4,  The  synovial  membrane.  5,  The  internal  lateral  ligament. 
6,  The  long  external  lateral  ligament.  7,  The  anterior  and  superior  ligament  that 
unites  the  fibula  to  the  tibia. 

Fig.  24.  2,  3,  The  ligaments  that  extend  from  the  clavir-le  (1)  to  the  scapula  (4." 
The  ligaments  5, 6,  extend  from  the  scapula  to  the  first  bone  of  the  arm. 

116.  Beside  the  synovial  membrane,  there  are  numerous 
smaller  sacs,  called  Iwr'sa,  mu-co'sa.  These  are  often  asso- 
ciated with  the  articulation.  In  structure;  they  are  analogous 
to  synovial  membranes,  and  secrete  a  simi/ar  fluid. 

11/5.  Describe  the  synovial  membrane.  116.  Describe  the  burste  mu-'-osaj 
u represented  by  fig.  23?  By  fig.  24? 


ANATOMY    OF    THE    BONES.  4 

117.  The  LIGAMENTS  are  composed  of  numerous  straighi 
fibres,  collected  together,  and   arranged  into  short  bands  of 
various  breadths,  or  so  interwoven  as  to  form  a  broad  layer, 
which  completely  surrounds  the  articular  extremities  of  the 
bones,  and  constitutes  a  capsular  ligament.     These  connect- 
ing bands  are  white,  glistening,  and  inelastic.     Most  of  the 
ligaments  are  found  exterior  to  the  synovial  membrane. 

118.  The  bones,  cartilages,  ligaments,  and  synovial  mem- 
brane are  insensible  when  in  health ;  yet  they  are  supplied 
with   organic   nerves,  as  well   as   with   arteries,  veins,  and 
lymphatics. 

Observation.  The  joints  of  the  domestic  animals  are  similar 
in  their  construction  to  those  of  man.  To  illustrate  this  part 
of  the  body,  a  fresh  joint  of  the  calf  or  sheep  may  be  used. 
After  divesting  the  joints  of  the  skin,  the  satin-like  bands,  or 
ligaments,  will  be  seen  passing  from  one  bone  to  the  other, 
under  which  may  be  observed  the  membranous  bag,  called  the 
capsular  ligament.  This  is  very  smooth,  as  it  is  lined  with 
the  soft  synovial  membrane,  beneath  which  will  be  seen  the 
cartilage,  that  may  be  cut  with  a  knife,  and  under  this  the 
rough  extremity  of  the  ends  of  the  bones. 

117.  Of  what  are  ligaments  composed  ?  What  is  the  appearance  of 
these  bands?  Where  are  they  found?  118.  With  what  vessels  are  the 
cartilages  and  ligaments  supplied?  How  can  the  structure  of  the  joint* 
be  explained  ? 


4:3  ANATOMY,    PHYSIOLOGY,  AND    HYGILNfc. 


CHAPTER     VI. 

PHYSIOLOGY    OF    THE    BONES. 

119.  THE  bones  are  the  framework  of  the  system.     By 
their  solidity  and  form,  they  not  only  retain  every  part  of  the 
fabric  in  its  proper  shape,  but  afford  a  firm  surface  for  the 
attachment  of  the  muscles  and  ligaments.     By  means  of  the 
bones,  the  human  frame    presents  to    the  eye  a  wonderful 
piece  of  mechanism,  uniting  the  most  finished  symmetry  of 
form   with  freedom  of  motion,  and  also  giving  security  to 
many  important  organs. 

120.  To  give  a  clear  idea  of  the  relative  uses  of  the  bones 
and  muscles,  we  will  quote  the  comparison  of  another,  though, 
as  in  other  comparisons,  there  are  points  of  difference.    The 
"  bones  are  to  the  body  what  the  masts  and  spars  are  to  the 
ship,  —  they  give  support  and  the  power  of  resistance.     The 
muscles  are  to  the  bones  what  the  ropes  are  to  the  masts  and 
spars.      The  bones   are  the  levers   of  the  system  ;   by  the 
action  of  the  muscles  their  relative  positions  are  changed.     As 
the  masts  and  spars  of  a  vessel   must  be  sufficiently  firm  to 
sustain  the  action  of  the  ropes,  so  the  bones  must  possess  the 
same    quality  to  sustain  the  action  of   the   muscles    in  the 
human  body." 

121.  Some  of  the  bones  are  designed  exclusively  for  the 
protection  of  the  organs  which  they  enclose.     Of  this  number 
are  those  that  form  the  skull,  the  sockets  of  the  eye,  and  the 
cavity  of  the  nose.     Others,  in  addition  to  the  protection  they 
give  to  important  organs,  are  useful  in  movements  of  certain 

119 — 128.  Give  the  physiology  of  the  bones.  119.  How  may  the  bones  be 
considered  ?  120.  To  what  may  the  bones  be  compared  ?  121.  Give  the 
difl'ercnt  offices  of  the  bones. 


PHYSIOLOGY    OF    THE    BO-VES.  4t» 

Kinds.  Of  this  class  are  the  bones  of  the  spinal  column,  and 
ribs.  Others  are  subservient  to  motion.  Of  this  class  are  the 
upper  and  lower  extremities. 

122.  The  bones  are  subject  to  growth  and  decay  ;  to  re- 
moval of  old,  useless  matter,  and  the  deposit  of  new  particles, 
as  in  other  tissues.     This  has  been  tested  by  the  following 
experiment.    Some  of  the  inferior  animals  were  fed  with  food 
that  contained  madder.     In  a  few  days,  some  of  the  animals 
were  killed,  and  their  bones  exhibited  an  unusually  reddish 
appearance.     The  remainder  of  the  animals  were,  for  a  few 
weeks,  fed  on  food    that   contained   no   coloring   principle. 
When  they  were  killed,  their  bones  exhibited  the  usual  color 
of  such  animals.     The  coloring  matter,  which  had  been  de- 
posited, had  been  removed  by  the  action  of  the  lymphatics. 

123.  The  extremities  of  the  bones  that  concur  in  forming 
a  joint,  correspond  by  having  their  respective  configuration? 
reciprocal.     They  are,  in  general,  the  one  convex,  and  the 
other  concave.     In  texture  they  are  porous,  and  consequr  nt- 
ly  more  elastic  than  if    more  compact.     These  are  covered 
with  a  cushion  of  cartilage.     The  elastic  character  of  these 
parts  acts  as  so  many  springs,  in  diminishing  the  jar  which 
important  organs  of  the  system  would  otherwise  receive. 

124.  The    synovial    membrane   secretes  a  viscous  fluid, 
which  is  called  syn-o'vi-a.     This  lubricating  fluid  of  the  joints 
enables  the  surfaces  of  the  bones  and  tendons  to  move  smooth- 
ly upon  each  other,  thus  diminishing  the  friction  consequent 
on  their  action. 

Observations.  1st.  In  this  secretion  is  manifested  the  skill 
and  omnipotence  of  the  Great  Architect ;  for  no  machine  of 
human  invention  supplies  to  itself,  by  its  own  operations,  the 
necessary  lubricating  fluid.  But,  in  the  animal  frame,  it  is 

122.  What  is  said  of  the  change  in  bones  ?  How  was  it  proved  that 
there  was  a  constant  change  in  the  osseous  fabri;?  123.  What  is  said  of 
the  extremities  of  the  bones  that  form  a  joint  ?  1  /I,  What  is  synovia  ?  Ifc> 
use?  What  is  said  of  this  lubricating  fluid  ? 


50 


ANATOMY,    PHYSIOLOGY,    AND 


supplied  in  proper  quantities,  and  applied  in  the  proper  place 
and  at  the  proper  time. 

2d.  In  some  cases  of  injury  and  disease,  the  synovial  fluid 
is  secreted  in  large  quantities,  and  distends  the  sac  of  the 
joint.  This  affection  is  called  dropsy  of  the  joint,  and  occurs 
most  frequently  in  that  of  the  knee. 

125.  The  function  of  the  ligaments  is  to  connect  and  bind 
together  the  bones  of  the  system.  By  them  the  small  bones 
of  the  wrist  and  foot,  as  well  as  the  large  bones,  are  as  se- 
curely fastened  as  if  retained  by  clasps  of  steel.  Some  of 
them  are  situated  within  the  joints,  like  a  centraf  cord,  01 
pivot,  (3,  fig.  26.)  Some  surround  it  like  a  hood,  and  con- 
rain  the  lubricating  synovial  fluid,  (8,  9,  fig.  25,)  and  sonw  io 
the  form  of  bands  at  the  side,  (5,  6,  fig.  23.) 


Fig.  25. 


Fig.  26. 


Fig.  25.    8,  9,  The  ligaments  that  extend  from  the  hip-bone  (6)  to  the  femur,  (5.) 
Fig.  26.    2,  The  socket  of  the  hip-joint.    5r  The  head  of  the  femur,  which  is  lodged 
tn  the  socket.    3,  Th«  ligament  within  the  socket. 

126.  By  the  ligaments  the  Tower  jaw  is  bound  to  the  tempo- 
ral bones,  and  the  head  to  the  neck.     They  extend  the  whole 

What  is  the  effect  -when  the  synovial  fluid  is  secreted  in  large  quanti- 
ties ?  125.  What  is  the  function  of  the  ligaments  ?  126.  Mention  how  th«r 
kones  of  the  system  are  connected. 


PHYSIOLOGY    OF    THE    BONL.3. 


51 


length  of  the  spinal  column,  in  powerful  bands,  on  the  outei 
surface,  between  the  spinal  bones,  and  from  one  spinous  process 
to  another.  They  bind  the  ribs  to  the  vertebrae,  to  the  trans- 
verse process  behind,  and  to  the  sternum  in  front ;  and  this 
to  the  clavicle  ;  and  this  to  the  first  rib  and  scapula  ;  and  this 
last  to  the  humerus. 

127.  They  also  bind  the  two  bones  of  the  fore-arm  at  the 
elbow-joint ;  and  these  to  the  wrist ;  and  these  to  each  other 
and  to  those  of  the  hand  ;  and  these  last  to  each  other  and 
to  those  of  the  fingers  and  thumb.  In  the  same  manner,  they 
bind  the  bones  of  the  pelvis  together ;  and  these  to  the  femur ; 
and  this  to  the  two  bones  of  the  leg  and  patella ;  and  so  on,  to 
the  ankle,  foot,  and  toes,  as  in  the  upper  extremities. 


Fig.  27.  1,  A  front  view  of  the  lateral  ligaments  of  the  finger-joints  2,  A  view 
of  the  anterior  ligaments  (a,  b,)  of  the  finger-joints.  3,  A  side  view  of  the  lateral 
ligaments  of  the  finger-joints. 

128.  The  different  joints  vary  in  range  of  movement,  and 
in  complexity  of  structure.  Some  permit  motions  in  all  di* 
rections,  as  the  shoulder ;  some  move  in  two  directions,  per- 
mitting only  flexion  and  extension  of  the  part,  as  the  elbow ; 
while  others  have  no  movement,  as  the  bones  of  the  head  in 
the  adult. 

Explain  fig.  27.  128.  Describe  the  variety  of  movements  in  the  dilfereut 
joUitfi. 


NATOMY,    PHYSIOLOGY,    AND    HYGIENE. 
Fig.  28 


Fig.  28.  1,  1,  The  spinal  column.  2,  The  skull.  3,  The  lower  jaw.  4,  Thesur- 
DUm.  5,  The  ribs.  6,  6,  The  cartilages  of  the  ribs.  7,  The  clavicle.  8,  The 
hniuorus.  9,  The  shoulder-joint.  10,  The  radius.  11,  The  ulna.  12,  The  elbow- 
joint.  13,  The  wrist.  14,  The  hand.  15,  The  haunch-bone.  16,  The  sacrum 
17,  The  hip-joint.  18,  The  thigh-bone.  19,  The  patella.  20,  The  knee-joint 
21,  The  fibula.  22,  The  tibia.  23,  The  ankle-joint.  24,  The  foot.  25,  26,  The 
ligaments  of  the  clavicle,  sternum,  and  ribs.  27,  28,  29,  Ths  ligaments  of  the  shoul 
der,  elbow,  and  wrist.  30,  The  large  artery  of  the  arm.  31,  The  ligaments  of  the 
hip-joint-  32,  The  large  blood-vessels  of  the  thigh.  33,  The  artery  of  the  leg.  34, 
3f>,  3fi,  The  ligaments  of  the  patella,  knee,  and  ankle. 

.     I.ct  the  pnpil,  in  f-iri/i  cf  topics,  review  the  anatomy  and  physiology  of  U»o 
.*.,,...;>  4»o...  ,.„    :>s>.  u<-  fi  ju:  4.;iUi>>;uiuil  outline  plates  No.  1  and  2. 


HYGIENE   OF   THE    BONES.  53 


CHAPTER     VII 

HYGIENE    OF    THE    BONES. 

129.  The  bones  increase  in  size  and  strength  by  use,  whih 
they  are  weakened  by  inaction.     Exercise  favors  the  deposi. 
tion   of   both  animal  and  earthy  matter,  by  increasing  the 
circulation  and  nutrition  in  this  texture.     For  this  reason,  the 
bones  of  the  laborer  are  dense  and  strong,  while  those  who 
neglect  exercise,  or  are  unaccustomed  to  manual  employment, 
are  deficient  in  size,  and  have  not  a  due  proportion  of  earthy 
matter  to  give  them  the  solidity  and  strength  of  the  laboring 
man. 

Observation.  The  tendons  of  the  muscles  are  attached 
near  the  extremities  of  the  bones.  Exercise  of  the  muscles 
increases  the  action  of  the  vessels  of  that  part  to  which  the 
tendons  are  attached,  and  thus  increases  the  nutrition  and  size 
of  this  portion  of  the  bone.  Hence  the  joints  of  an  indus- 
trious mechanic  or  farmer  are  larger  than  those  of  an  indi- 
vidual who  has  not  pursued  manual  vocations. 

130.  The  gelatinous  bones  of  the   child   are  not  so  well 
adapted  for  labor  and  severe  exercise  as  those  of  an  adult. 
1st.  They  are  liable  to  become  distorted.     2d.  They  are  con- 
solidated by  the  deposition  of  earthy  material  before  they  are 
fully  and  properly  developed.     If  a  young  animal,  as  the 
colt,  be  put  to  severe,  continued  labor,  the  deposition  of  earthy 

129 — 148.  Give  the  hygiene  of  the  bones.  129.  What  effect  has  exercise 
upon  the  bones  ?  What  effect  has  inaction  ?  Why  are  the  joints  of  the 
industrious  farmer  and  mechanic  larger  than  those  of  a  person  unac- 
customed to  manual  employment  ?  130.  Give  the  first  reason  why  the 
bones  of  the  child  are  not  adapted  to  severe  exercise.  The  second 
reason 

5* 


54  ANATOMY,    PHYSIOLOGY,    AN1>    HYGIENE. 

matter  is  hastened,  and  the  bones  are  consolidated  before 
they  attain  full  growth.  Such  colts  make  small  and  inferior 
animals.  Similar  results  follow,  if  a  youth  is  compelled  t 
toil  unduly  before  maturity  of  growth  is  attained.  On  the 
other  hand,  moderate  and  regular  labor  favors  a  healthy 
development  and  consolidation  of  the  bones. 

131.  The  kind  and  amount  of  labor  should  be  adapted  to  the 
age,  health,  and  development  of  the  bones.     Neither  the  flexi- 
ble bones  of  the  child  nor  the  brittle  bones  of  the  aged  man 
are  adapted,  by  their  organization,  to  long-continued,  and  hard 
labor.     Those  of  the  one  bend  too  easily,  while  those  of  the 
other  fracture  too  readily.     In  middle  age,  the  proportions  of 
animal  and  earthy  matter  are,  usually,  such  as  to  give   the 
proper  degree  of  flexibility,  firmness,  and  strength  for  labor, 
with  little  liability  to  injury. 

132.  The  imperfectly  developed  bones  of  the  young  child 
will  not  bear  long-continued  exertions  or  positions  without 
injury.     Hence  the  requisitions  of  the   rigid  disciplinarian  of 
schools,  are  unwise  when  he  compels  his  pupils  to  remain  in 
one  position  for  a  long  time.     He  may  have  a  "  quiet  school ; " 
but,  not  unfrequently,  by  such  discipline,  the  constitution   is 
impaired,  and  permanent  injury  is  done  to  the  pupils. 

133.  The  lower  extremities,  in  early  life,  contain  but  a  small 
proportion  of  earthy  matter  ;  they  bend  when  the  weight  of 
the  body  is  thrown  upon  them  for  a  long  time.     Hence,  the 
assiduous  attempts  to  induce  children  to  stand  or  walk,  either 
naturally   or  artificially,  when   very   young,  are  ill  advised, 
and  often    productive  of  serious  and  permanent  evil.     The 
u  bandy"  or  bow  legs  are  thus  produced. 

What  effect  has  moderate,  regular  labor  upon  the  growing  youth  ? 
131.  What  remark  respecting  the  kind  and  amount  of  labor  ?  At  what  age 
are  the  bones  best  fitted  for  labor  ?  132.  What  effect  has  long-continued 
exertions  or  positions  on  the  bones  of  a  child?  What  is  said  of  the  requi- 
sitions of  some  teachers,  who  have  the  famed  "  quiet  schools  "  ?  133.  Why 
should  not  the  child  be  induced  to  stand  or  walk,  either  naturally  or  artiti 
eially,  at  too  early  an  aee  ? 


HYGIENE    OF    THE    BONES. 


55 


134.  The  benches  or  chairs  for  children  in  a  school-room 
should  be  of  such  a  height  as  to  permit  the  feet  to  rest  on  tliejloor. 
If  the  bench  is  so  high  as  not  to  permit  the  feet  to  rest  upon 
the  floor,  the  weight  of  the  limbs  below  the  knee  may  cause 
the  flexible  bone  of  the  thigh  to  become  curved.  The  child 
thus  seated,  is  inclined  to  lean  forward,  contracting  an  injuri- 
ous and  ungraceful  habit.  Again,  when  the  feet  are  not  sup- 


Fig.  29. 


Fig.  30. 


Fig.  29.  The  position  assumed  when  the  seat  is  of  proper  height,  and  the  feet 
supported. 

Fig.  30.  The  position  a  child  naturally  assumes  when  the  seat  is  so  high  that  the 
feet  are  not  supported. 

ported,  the  child  soon  becomes  exhausted,  restless,  and  unfit 
for  study.  In  the  construction  of  a  school-room,  the  benches 
should  be  of  different  heights,  so  as  to  be  adapted  to  the  dif- 
ferent pupils,  and  they  should  also  have  appropriate  backs. 

Ih4.  "What  is  said  of  the  benches  or  chairs  in  a  school-room?  "What  ia 
represented  by  fig.  29  ?  By  fig.  30  ?  What  is  the  effect  when  the  lower 
limbo  are  not  supported  ? 


5(>  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

135.  Compression  of  the  chest  should  be  avoided.  In  chil- 
dren, and  also  in  adults,  the  ribs  are  very  flexible,  and  a  smal 
amount  of  pressure  will  increase  their  curvature,  particularly  at 
the  lower  part  of  the  chest,  and  thus  lessen  the  size  of  this 
cavity.  The  lower  ribs  are  united  to  the  breast-bone,  by  long, 
yielding  cartilages,  and  compression  may  not  only  contract 
>he  chest,  but  an  unseemly  and  painful  ridge  may  be  pro- 
duced, by  the  bending  of  the  cartilages,  on  one  or  both  sides 
of  the  sternum. 


Fig.  31. 


Fig.  32. 


Fig.  31. 
Fig.  32. 


A  natural  and  well-proportioned  chest. 
A  chest  fashionably  deformed. 


136.  Again,  the  cartilages  on  one  side  may  be  bent  out- 
ward, while  those  on  the  opposite  side  are  bent  inward,  thus 
forming  a  depression  parallel  with  the  sternum.  In  some  in- 
stances, the  anterior  extremity  of  the  lower  ribs  on  each  side 


13-5.  Why  should  compression  of  the  chest  be  avoided?     What  is  repre- 
sented by  fig.  31  ?     By  fig.  32? 


HYGIENE    OF    THE    BONES.  57 

are  brought  nearly  or  quite  together.  In  these  instances,  the 
movable  extremities  of  the  ribs  are  drawn  down  toward  the 
haunch-bones,  while  the  space  between  the  ribs  is  lessened. 
All  this  may  be  effected  by  tight  or  "  snug  "  clothing.  There- 
fore the  apparel  of  a  child  should  be  loose,  and  supported 
over  the  shoulders,  to  avoid  the  before-mentioned  evils.  The 
same  may  be  said  of  the  clothing  for  adults. 

137.  The  erect  position  in  sitting  and  standing  should  be 
assiduously  observed.     The  spinal  column,  in  its  natural  po- 
sition, curves  from  front  to  back,  but  not  from  side  to  side 
The  admirable  arrangement  of  the  bones,  alternating  with  car- 
tilages, permits  a  great  variety  of  motions  and  positions ;  and 
when  the  spine  is  inclined  to  either  side,  the  elasticity  of  its 
cartilages  tends  to  restore  it  to  its  natural  position.     For  this 
reason  we  may  incline  the  spinal  column  in  any  direction  foi 
a  short  time,  without  danger  of  permanent  curvature,  if,  af- 
terward, the  erect  position  is  assumed.* 

138.  Bui  if  a  stooping  position,  or  a  lateral  curved  posture, 
is  coiu'iiuai  for  a  long  time,  the  spinal  column  does  not  easily 
recover  its  proper  position,  for  the  compressed  edges  of  the 
'cartilages  lose  their  power  of  reaction,  and  finally  one  side  of 
the  cartilage  becomes  thinned  ,  while  the  other  is  thickened  ; 
and  these  wedge-shaped  cartilages  produce  a  permanent  cur- 
vature of  th3  spinal  column.     In  a  similar  way,  the  student, 
seamstress,  artisan,  and  mechanic  acquire  a  stooping  position, 
and  become  round  shouldered,  by  inclining  forward  to  bring 
their  books  or  work  nearer  the  eyes. 

139.  Pupils,  while  writing,  drawing,  and  sometimes  whi'3 


Compare  1,  1,  Fig.  28,  with  2,  2,  2,  Fig.  48. 


136.  May  simply  "  snug  "  clothing  compress  the  cartliages  ?  How  should 
the  apparel  of  a  child  be  worn  ?  137.  In  what  direction  does  the  spinal 
column,  in  its  natural  position,  curve  ?  "What  restores  it  to  its  natural 
position  when  curved  laterally  ?  138.  What  is  the  effect  if  a  lateral  curved 
position  of  the  spinal  column  is  continued  for  a  long  time  ?  139.  When 
one  shoulder  is  elevated  for  a  long  time,  what  is  the  effect  upon  the 
spinal  column  ? 


58 


ANATOMY,    PHYSIOLOGY,    AND    1.YGIENE. 


studying,  frequently  incline  the  spinal  column  to  one  side,  in 
order  to  accommodate  themselves  to  the  desks  at  which  they 
are  seated.  Often,  these  are  higher  than  the  elbow  as  it  hangs 
from  the  shoulder  while  at  rest.  This  attitude  elevates  one 
shoulder  while  it  depresses  the  other ;  consequently,  the  upper 

Fig.  33. 


Fig.  33.  The  table  is  of  proper  height,  the  position  is  correct,  and  the  spinal  co.umn, 
1,  1,  is  straight,  while  the  shoulders  are  of  equal  height.. 

part  of  the  spinal  column  is  inclined  toward  the  elevated 
shoulder,  and  the  lower  part  is  curved  in  the  opposite  direc- 
tion, giving  the  form  of  the  letter  S  to  the  supporting  column 
of  the  body. 


What  does  fig.  33  represent  ? 


HYGIENE    OF    THE    BONES. 


59 


Experiment.  Let  a  pupil  be  placed  at  a  desk  or  table  with 
one  elbow  raised,  as  is  frequently  seen  while  writing,  or  at 
study,  and  observe  the  condition  of  the  shoulder  and  spinal 
column  in  this  position.  Place  another  pupil  at  a  table  no 
higher  than  the  elbow  when  it  hangs  by  the  side  while  sitting, 
and  observe  the  appearance  of  the  shoulders  and  spinal  column. 
By  a  comparison  of  the  two  attitudes,  the  preceding  remarks 
will  be  comprehended  and  appreciated. 

Fig.  34. 


Fig.  34.  The  table  is  too  high,  and  the  position  is  oblique  and  impioper.  Thn 
right  shoulder  is  seen  higher  than  the  left,  while  the  spinal  column,  1,  1,  exhibits 
three  curves. 

140.    One  shoulder  may  be  elevated,  and  no  injurious  results 

What  experiment  is  mentioned?  "What  does  fig.  34  represent  ?  140.  How 
can  one  shoulder  be  elevated  and  no  injurious  results  follow  ? 


l>0  ANATOMY,  PHYSIOLOGY,    AND    HYGIENE. 

follow,  provided  care  is  taken  not  to  keep  it  in  the  raised  posi 
tion  too  long,  or  if  the  opposite  shoulder  is  elevated  for  the 
same  period  of  time.  The  right  shoulder  projects  more  fre- 
quently than  the  left.  This  arises  from  the  greater  use  of  the 
right  hand  with  the  shoulder  elevated,  and  not  unfrequently 
the  oblique  positions  assumed  in  performing  the  daily  voca- 
tions of  life.  With  proper  care,  and  by  calling  into  action 
the  left  shoulder,  this  deformity  can  be  prevented. 

Fig.  35. 


Fig.  3o.  A  representation  of  a  deformed  trunk. 

141.  The  loss  of  symmetry  and  diminution  of  height  from 
deformed  spines  are  minor  considerations,  compared  with  the 
distortions  that  the  chest  experiences,  thereby  impairing  res- 
piration and  inducing  diseases  of  the  heart  and  lungs.  The 

Why  does  the  right  shoulder  project  more  frequently  than  the  left  ?  How 
can  this  deformity  be  prevented  ?  141.  What  is  said  of  deformed  spinaJ 
columns  ? 


HYGIENE    OF    THE    BONES  H| 

invasion  of  the  functions  of  these  two  important  organs  lessens 
the  vitality  of  the  whole  system,  and  causes  general  ill  health. 
Again,  the  curvature  of  the  spinal  column  is  frequently  at- 
tended by  irritation  and  disease  of  the  spinal  cord. 

142.  Eminent  physicians,  both  in  this  country  and  France 
state  that  not  more  than  one  female  in  ten,  who  has  been  fash- 
ionably educated,  is  free  from  deformities  of  the  shoulder  or 
spinal  column.     Teachers,  as  well  as  mothers,  should  notice 
the  positions  of  the  child  in   performing  the  tasks  allotted  to 
it,  whether  studying  or  pursuing  any  employment.     The  fee- 
bler the  organization  of  the  child,  the  more  frequently  should 
there  be  a  change  of  position. 

143.  When  a  slight  projection  of  the  shoulder,  with  a  cur- 
vature of  the  spine,  exists,  it  can  be  improved  by  walking  with 
a  book,  or  something  heavier,  upon  the  head  ;  to  balance  which, 
the  spinal  column  must  be  nearly  erect.     Those  people  that 
carry  burdens  upon  their  heads  seldom  have  crooked  spines. 

Observation.  Persons  from  the  North,  in  travelling  through 
the  Southern  States,  are  surprised  to  see  the  heavy  burdens 
that  the  porters  carry  on  their  heads.  It  is  not  unusual  to  see 
them  walking  at  a  rapid  pace,  with  one  or  two  trunks,  weigh- 
ing fifty  or  eighty  pounds  each,  upon  their  heads.  Occasion- 
ally, we  meet  an  itinerant  toy-man,  with  his  tray  of  fragile 
merchandise  upon  his  head,  walking  with  as  much  apparent 
security,  as  though  his  toys,  or  images,  were  in  his  hands. 
This  is  the  easiest  method  of  carrying  burdens,  because  the 
position  of  the  head  and  spinal  column  is  erect. 

144.  If  the  animal  and  earthy  matter  of  the  bones  is  not 
deposited  in  proper  proportions,  they  are  deficient  in  strength. 
If  the    gelatin   predominates,  the  bones  are  weak,  and    be- 


142.  What  statement  by  eminent  physicians  respecting  deformities  of  the 
spine  ?  What  caution  to  teachers  and  mothers  ?  143.  Why  should  we 
stand  and  sit  erect?  How  may  slight  deformities  of  the  spine  be  pie- 
vonted  ?  What  is  frequently  noticed  in  travelling  South  ?  144.  What  is 
the  ettV>ct  upon  the  hme--  'viicn  the  gelatin  preponderates  ? 


6^  ANATOMY,  -PHYSIOLOGY,    AND    HYGIENE. 

come  distorted.  When  nutrition  is  defective  in  the  cylindri 
cal  bones,  the  heads  are  generally  enlarged,  and  the  shafts 
crooked  ;  if  in  the  spinal  column,  it  may  be  curved ;  or  in  the 
cranium,  it  may  be  enlarged.  This  disease  is  familiarly  known 
by  the  name  of  rickets.  It  is  most  common  among  those  who 
nave  poor  and  insufficient  food,  live  in  dark,  damp  rooms,  and 
breathe  a  vitiated  air.  The  prevention  and  remedies  for  this 
disease  are  cleanliness,  regular  exercise,  pure  air,  and  nutri- 
tious food. 

145.  When  a  bone  is  broken,  some  days  elapse  before  the 
ubstance  that  reunites  it  is  thrown  out  from  the  blood.  In 
young  persons,  it  may  be  secreted  during  the  second  or  third 
week,  and  in  individuals  advanced  in  life,  usually  during  the 
third  and  fourth  week.  When  the  bone  is  uniting,  during  the 
second,  third,  or  fourth  week,  the  attention  of  a  surgeon  is 
more  needed  than  during  the  first  week.  At  this  time,  the 
ends  of  the  bone  should  be  placed  together  with  accuracy, 
which  requires  the  careful  application  of  proper  dressing. 
After  the  bones  have  united,  it  will  take  some  weeks  to 
consolidate  the  uniting  material  and  render  the  "  callus,"  or 
union,  firm.  During  this  time,  the  limb  should  be  used  with 
care. 

Observation.  When  a  bone  is  fractured,  a  surgeon  is  imme- 
diately called,  and  the  bone  is  "  set."  While  the  limb  remains 
swelled  and  painful,  the  surgeon  is  required  to  attend  and 
keep  the  dressings  (bandages  and  splints)  on.  When  the 
swelling  has  abated,  and  the  pain  subsided,  frequently  the 
patient  intimates  to  the  surgeon  that  his  services  can  be 
dispensed  with,  as  the  "  limb  is  doing  well."  This  is  the  most 
important  period,  as  the  bone  is  uniting,  and,  unless  the  ends 
are  nicely  adjusted,  the  dressing  properly  applied,  the  person 

What  is  one  cause  of  rickets  ?  What  are  the  prevention  and  remedies 
for  this  disease?  145.  Does  the  time  vary  when  the  reuniting  substance 
of  the  bone  is  secreted  from  the  blood  ?  When  is  the  surgeon's  care  most 
needed  ?  Why  ? 


HYGIENE    OF 


will  find,  on  recovery,  a  shortened  and  crooked  limb.     The 
surgeon  is  then  censured,  when  he  is  not  blamable. 

146.  It  is  seldom  that  a  bone  is  displaced  without  injury 
to  the  connecting  ligaments  and  membranes.     When  these 
connecting   bands  are    lacerated,  pain,  swelling,   and    other 
symptoms  indicating  inflammation  succeed,  which  should  be 
removed  by  proper  treatment,  directed  by  a  surgical  adviser. 

147.  In  sprains,  but  few,  if  any,  of  the  fibres  of  the  con- 
necting ligaments  are  lacerated  ;  but  they  are  unduly  strained 
and  twisted,  which  occasions  acute  pain  at  the  time  of  the 
injury.    This  is  followed  by  inflammation  and  weakness  of  the 
joints.     The  treatment  of  these  injuries  is  similar  to  that  of  a 
dislocated  bone  after  its  reduction.     The  most  important  item 
in  the  treatment  during  the  few  first  days,  is  rest. 

148.  In  persons  of  scrofulous  constitutions,  and  those   in 
whom  the  system  is  enfeebled  by  disease,  white  swellings  and 
other  chronic  diseases  of  the  joints  frequently  succeed  sprains. 
Such  persons  cannot  be  too  assiduous  in  adopting  a  proper  and 
early  treatment  of  injured  joints. 

146.  What  parts  are  injured  in  the  displacement  of  a  bone  ?  147.  What 
causes  the  acute  pain  in  sprains  ?  What  is  a  good  remedy  for  this  kind 
of  injury  ?  148.  What  caution  to  persons  of  scrofulous  constitutions  ? 


64  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE 

CHAPTER    VIII 

THE    MUSCLES. 

149.  ALL  the  great  motions  of  the  body  are  caused  by  the 
movement  of  some  of  the  bones  which  form  the  framework 
of  the  system ;  but  these,  independently  of  themselves,  have 
not   the    power  of  motion,  and   only  change  their  position 
through  the  action  of  other  organs  attached  to  them,  which,  by 
contracting,  draw  the  bones  after  them.     In  some  of  the  slight 
movements,  as  the  winking  of  the  eye,  no  bones  are  displaced. 
These   moving,  contracting  organs   are   the  Mus'cles,  (lean 
meat.) 

ANATOMY  OF  THE  MUSCLES. 

150.  The  MUSCLES,  by  their  size  and  number,  constitute  the 
great  bulk  of  the  body,  upon  which  they  bestow  form  and 
symmetry.     In  the  limbs,  they  are  situated  around  the  bones, 
which  they  invest  and  defend,  while  they  form,  to  some  of  the 
joints,  their  principal  protection.     In  the  trunk,  they  are  spread 
out  to  enclose  cavities,  and  constitute  a  defensive  wall,  capa- 
ble of  yielding  to  internal  pressure,  and  reassuming  its  origi- 
nal state. 

151.  In  structure,  a  muscle   is   composed  of  fas-cic'u-h 
(bundles  of  fibres)  of  variable  size.     These  are  enclosed  in  a 
cellular  membranous  investment,  or  sheath.     Every  bundle 
composed  of  a  number  of  small  fibres,  and  each  fibre  con 
sists  of  a  number  of  filaments,  each  of  which  is  enclosed  in 

149.  How  are  all  the  motions  of  the  body  produced  ?  What  are  these 
motor  organs  called  ?  150 — 160.  Give  the  anatomy  of  the  muscles 
'50.  What  is  said  of  the  muscles?  151.  Give  their  structure. 


ANATOMY    OF    THE    MUSCLES. 


a  delicate  sheath.  Toward  the  extremity  of  the  organ  the 
muscular  fibre  ceases,  and  the  cellular  structure  becomes 
aggregated,  and  so  modified  as  to  constitute  ten'dons,  (cords,) 
by  which  the  muscle  is  tied  to  the  surface  of  the  bone.  The 
union  is  so  firm,  that,  under  extreme  violence,  the  bone  will 
sooner  break  than  permit  the  tendon  to  separate  from  its 
attachment.  In  some  situations,  there  is  an  expansion  of  the 
tendon,  in  the  manner  of  a  membrane,  called  Ap-o-neu-ro'sis, 
or  Fasfci-a. 

Observation.  The  pupil  can  examine  a  piece  of  boiled 
beef,  or  the  leg  of  a  fowl,  and  see  the  structure  of  the 
fibres  and  tendons  of  a  muscle. 

Fig.  36. 


/ 
i 


12  34 

Fig.  36.  1,  A  representation  of  the  direction  and  arrangement  of  the  fibres  in  A 
fusiform,  or  spindle-shaped  muscle.  2,  In  a  radiated  muscle.  3,  In  a  pennifcrm 
muscle.  4,  In  a  bipenniform  muscle.  *,  t,  The  tendons  of  a  muscle. 

152.  Muscles  present  various  modifications  in  the  arrange- 
ment of  their  fibres,  as  relates  to  their  tendinous  structure. 
Sometimes  they  are  completely  longitudinal,  and  terminate,  at 
each  extremity,  in  a  tendon,  the  entire  muscle  being  spindle- 
shaped.  In  other  situations,  they  are  disposed  like  the  rays  of 

How  are  tendons  or  cords  formed  ?  What  is  the  expansion  of  a  tendon 
called  ?  How  can  the  structure  of  muscles  and  their  fibres  be  shov  n  ? 
What  does  fig.  36  represent  ?  152.  Give  the  different  arrangements  *f 

muscular  iibres. 

6* 


66  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

a  fan,  converging  to  a  tendinous  point,  and  constituting  a 
radi-ate  muscle.  Again  they  are  perini-form,  converging, 
like  the  plumes  of  a  pen,  to  one  side  of  a  tendon,  which  runs 
the  whole  length  of  the  muscle  ;  or  they  are  bi-pen'ni-form, 
converging  to  both  sides  of  the  tendon. 

153.  In  the  description  of  a  muscle,  its  attachments  are 
expressed   by  the   terms  "origin"    and   "insertion."      The 
term  origin  is  generally  applied  to  the  more  fixed  or  centra] 
attachment,  or  to  the  point  toward  which  motion  is  directed ; 
while  insertion  is  assigned  to  the  more  movable  point,  or  to 
that  most  distant  from  the  centre.     The  middle,  fleshy  portion 
is  called  the  "  belly,"  or  "  swell."     The  color  of  a  muscle 
is  red  in  warm-blooded  fish  and  animals ;  and  each  fibre   is 
supplied  with  arteries,  veins,  lymphatics,  and  both  sensitive 
and  motor  nervous  filaments. 

154.  The  FASCIA  is  of  various  extent  and  thickness,  dis- 
tributed through  the  different  regions  of  the  body,  for  the  pur- 
pose of  investing  and  protecting  the  softer  and  more  delicate 
organs.     An  instance  is  seen  in  the    membrane  which  en- 
velopes a  leg  of  beef,  and  which  is  observed  on  the  edges  of 
the  slices  when  it  is  cut  for  broiling.     When  freshly  exposed, 
it  is  brilliant  in  appearance,  tough,  and  inelastic.    In  the  limbs- 
it  forms  distinct  sheaths  to  all  the  muscles. 

155.  This  tendinous  membrane  assists  the  muscles  in  their 
action,  by  keeping  up  a  tonic  pressure  on  their  surface.     It 
o  ids  materially  in  the  circulation  of  the  fluids,  in  opposition 
to  the  laws  of  gravity.     In  the  palm  of  the  hand  and  sole  of 
the  foot,  it  is  a  powerful  protection  to  the  structures  that  enter 
into  the  formation  of  these   parts.     In  all  parts  of  the  system, 
the  separate  muscles  are  not  only  invested  by  fascia,  but  they 

153.  What  is  meant  by  the  origin  of  a  muscle  ?  The  insertion  ?  The 
swell  ?  What  is  the  color  of  muscles  ?  With  what  is  each  muscular  fibre 
supplied  ?  154.  What  is  said  of  fascia  ?  What  is  its  appearance  when 
freshly  exposed  ?  155.  What  effect  has  it  on  the  muscles  ?  Give  othe* 
uses  of  the  fascia. 


ANATOMY    OF    THE    MUSCLES. 


67 


arc  arranged  in  layers,  one  over  another.  The  sheath  or  each 
muscle  is  loosely  connected  with  another,  by  the  cellular 
membrane. 

156.  The  interstices  between  the  different  muscles  are 
filled  with  adipose  matter,  or  fat.  This  is  sometimes  called 
the  packing  of  the  system.  To  the  presence  of  this  tissue, 
youth  aue  indebted  for  the  roundness  and  beauty  of  their 

limbs. 

Fig.  37. 


Fig.  o7.  A  transverse  section  of  the  neck.  The  separate  muscles,  as  they  aie 
Arranged  in  layers,  with  their  investing  fasciae,  are  beautifully  represented.  As 
the  system  is  symmetrical,  figures  are  placed  only  on  one  side.  In  the  trunk  the 
muscles  are  arranged  in  layers,  surrounded  by  fascis,  as  in  the  neck.  The  same 
is  true  of  the  muscles  of  the  upper  and  lower  limbs. 

12,  The  trachea,  (windpipe.)  13,  The  oesophagus,  (gullet.)  14,  The  carotid  artery  and 
jugular  vein.  28,  One  of  the  bones  of  the  spinal  column.  The  figures  that  are  placed 
in  the  white  spaces  represent  some  of  the  fascia; ;  the  other  figures  indicate  muscles. 

157.  The  muscles  may  be  arranged,  in  conformity  with  the 
general  division  of  the  body>  into  four  parts :  1st.  Those  of 
the  Head  and  Neck.  2d.  Those  of  the  Trunk.  3d.  Those 
of  the  Upper  Extremities.  4th.  Those  of  the  Lower  Ex- 
tremities. 

156.  Give  a  reason  why  the  limbs  of  youth  are  rounder  than  those  of  the 
aged.  Describe  fig.  37. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 
Fig.   38. 


Fig.  38.  The  superficial  layer  of  muscles  on  ..  ..d  neck.  1, 1,  The  occipito 

frontalis  muscle.  2,  The  orbicularis  palpebrar  .  6,  The  levator  labii  superioria 
7,  The  levator  anguli  oris.  8,  The  zygomaticus  minor.  9,  The  zygomaticus  major 
10,  The  masseter.  11,  The  depressor  labii  superioris.  13,  The  orbicularis  oria 
15,  The  depressor  anguli  oris.  16,  Tht  depressor  labii  inferioris.  18,  The  sterno- 
hyoideus.  19,  The  platysma-myodes  ),  The  superior  belly  of  the  omo-hyoideus. 
21,  The  sterno-cleido  mastoideus.  2L  The  scalenus  medius.  23,  The  inferior  belly 
of  the  omo-hyoideus.  24,  The  trapezius.* 

Practical  Explanation.  The  muscle  1,  1,  elevates  the  eyebrows.  The  muscle  a 
closes  the  eye.  The  muscle  6  elevates  the  upper  lip.  The  muscles  7,  8,  9,  elevate 
the  angle  of  the  mouth.  The  muscle  10  brings  the  teeth  together  when  eating.  The 
muscle  11  depresses  the  upper  lip.  The  muscle  13  closes  the  mouth.  The  muscle 
15  depresses  the  angle  of  the  mouth.  The  muscle  16  draws  down  the  lower  lip. 
The  muscles  18,  19,  20.  23,  depress  the  lower  jaw  and  larynx  and  elevate  the  sternum. 
The  muscle  21,  when  both  sides  contract,  draws  the  head  forward,  or  elevates  the 
sternum  ;  when  only  one  contracts,  the  face  is  turned  one  side  toward  the  opposite 
shoulder.  The  muscles  18,  19,  20,  21,  22,  23,  24,  aid  in  respiration. 

*  In  the  plates  illustrating  the  muscular  system,  the  names  of  such  muscles  are 
given  as  are  referred  to  in  the  paragiaph  "  Practical  Explanation."  These  names  nco-1 
not  be  committed  to  memory.  If  a  pupil  wishes  to  acquire  a  knowledge  of  the 
general  attachment  of  the  muscles  represented  in  the  plates,  he  can  do  so  by  r-om~ 
paring  the  muscular  plate  with  that  of  the  skeleton,  (fig.  28.) 


ANATf  MY    OF    THE    MUSCLES.  69 

Observation.  When  we  are  sick,  and  cannot  take  food, 
the  body  is  sustained  by  absorption  of  the  fat.  The  removal 
of  it  into  the  blood  causes  the  sunken  cheek,  hollow  eye,  and 
prominent  appearance  of  the  bones  after  a  severe  illness. 

158.  The  number  of  muscles  in  the  human  body  is  more 
than  five  hundred;  in  genera),  they  form  about  the  skeleton 
two  layers,  and  are  distinguished  into  superficial  and  deep- 
seated  muscles.  Some  of  the  muscles  are  voluntary  in  their 
motions,  or  act  under  the  government  of  the  will,  as  those 
which  move  the  fingers,  limbs,  and  trunk  ;  while  others  are 
involuntary,  or  act  under  the  impression  of  their  proper  stimu- 
lants, without  the  control  of  the  individual,  as  the  heart. 

Observations.  1st.  The  abdominal  muscles  are  expiratory, 
and  the  chief  agents  for  expelling  the  residuum  from  the  rec- 
tum, the  bile  from  the  gall  bladder,  the  contents  of  the  stomach 
and  bowels  when  vomiting,  and  the  mucus  and  irritating  sub- 
stances from  the  bronchial  tubes,  trachea,  and  nasal  passages 
by  coughing  and  sneezing.  To  produce  these  effects  they  all 
act  together.  Their  violent  and  continued  action  sometimes 
produces  hernia,  and,  when  spasmodic,  may  occasion  ruptures 
of  the  different  organs. 

2d.  The  contraction  and  relaxation  of  the  abdominal  mus- 
cles and  diaphragm  stimulate  the  stomach,  liver,  and  intestines 
to  a  healthy  action,  and  are  subservient  to  the  digestive  powers. 
If  the  contractility  of  their  muscular  fibres  is  destroyed  or 
impaired,  the  tone  of  the  digestive  apparatus  will  be  diminished, 
as  in  indigestion  and  costiveness.  This  is  frequently  attended 
by  a  displacement  of  those  organs,  as  they  generally  gravitate 
towards  the  lower  portion  of  the  abdominal  cavity,  when  the 
sustaining  muscles  lose  their  tone  and  become  relaxed. 

What  causes  the  hollow  eye  and  sunken  cheek  after  a  severe  sickness  ? 
158.  How  many  muscles  in  the  human  system  ?  Into  how  many  layers  are 
they  arranged  ?  "What  is  a  voluntary  muscle  ?  Give  examples.  What  ia 
an  involuntary  muscle  ?  Mention  examples.  Give  observation  1st,  respect- 
ing the  use  of  the  abdominal  muscles  ?  Observation  2d. 


70 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 
Fig.    39. 


mmm 


I 


Fig  39  A  front  view  of  the  muscles  of  the  trunk.  On  the  left  side  the  superficia 
layer  is  sesn  ;  on  the  right,  the  deep  layer.  1,  The  pectonilis  major  muscle.  2,  The 
deltoid  muscle.  6,  The  pectoraMs  minor  muscle.  9,  The  coracoid  process  of  the 
scapula.  11,  The  external  intercostal  muscle.  12,  The  external  oblique  muscle 
13,  Its  aponeurosis.  16,  The  rectus  muscle  of  the  right  side.  18,  The  interna. 
oblique  muscle. 

Practical  Explanation.  The  muscle  1  draws  the  arm  by  the  side,  and  across  the 
chest,  and  likewise  draws  the  scapula  forward.  The  muscle  2  elevates  the  arm.  The 
muscle  6  elevates  the  ribs  when  the  scapula  Is  fixed,  or  draws  the  scapula  forward 
and  downward  when  the  ribs  are  fixed.  The  muscles  12,  16,  18,  bend  the  body  for- 
ward or  elevate  the  hips  when  the  muscles  of  both  sides  act.  They  likewise  depress 
the  ribs  in  expiration.  When  the  muscles  on  only  one  side  act,  the  body  is  twisted  to 
the  same  side. 


Explain   fig.  39.     Give   the    function   of  some   of  the  most  prominent 
muscles,  from  this  figure. 


.^w-v-wv 


* 


-  M^K . 

ANATOMY    OF    THE    MUSCLES. 

^^^U 


g.  40, 


_ 


pAfWV'^       Qj2. 


Fig.  40.  A  lateral  view  of  the  muscles  of  the  trunk.  3,  The  upper  part  of  tha 
external  oblique  muscle.  4,  Two  of  the  external  intercostal  muscles.  5,  Two  of  the 
internal  intercostals.  6,  The  transversalis  muscle.  7,  Its  posterior  aponeurosia. 
8,  Its  anterior  aponeurosis.  11,  The  right  rectus  muscle.  13,  The  crest  of  the 
iliuin,  or  haunch-bone. 

Practical  Explanation.  The  rectus  muscle,  11,  bends  the  thorax  upon  the  abdomen 
when  the  lower  extremity  of  the  muscle  is  the  fixed  point ;  but  when  the  upper  ex- 
tremity is  the  fixed  point,  the  effect  is  to  bring  forward  and  raise  the  pelvis  and  lower 
extremities.  They  likewise  depress  the  ribs  in  respiration.  The  transverse  mu  scle, 
6,7,  8,  lessens  the  cavity  of  the  abdomen,  and  presses  the  intestines^"  stomach,  and 
liver  upward,  against  the  diaphragm,  in  expiration. 

3d.  The  region  of  the  back,  in  consequence  of  its  extent,  is 
common  to  the  neck,  the  upper  extremities,  and  the  abdomen. 
The  muscles  of  which  it  is  composed  are  numerous,  and  are 
arranged  in  six  layers. 


What  is  represented  by  fig.  40? 
*/n."".r.lc3  represented  by  this  figure. 


Give  the  function  of  some  of  the 


r-z 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 
Fig.   41. 


Fig  41  The  first,  second,  and  part  of  the  third  layer  of  muscles  of  the  back 
5  he  first  layer  is  shown  on  the  right,  and  the  second  on  the  left  side.  1,  The  tra 
l»  zius  muscle.  2,  The  spinous  processes  of  the  vertebrae.  3,  The  acromion  process 
ar.d  spine  of  the  scapula.  4,  The  latissimus  dorsi  muscle.  5,  The  deltoid  muscle. 
7,  The  external  oblique  muscle.  8,  The  gluteus  medius  muscle.  9,  The  glutens 
maximus  muscle.  11,  12,  The  rhomboideus  major  and  minor  muscles.  15,  The 
vertebral  aponeurosis.  16,  The  serratus  posticus  inferior  muscle.  22,  The  serratus 
magnus  muscle.  23,  The  internal  oblique  muscle. 

Practical  Explanation.  Tho  muscles  1, 11, 12,  draw  the  scapula  back  toward  the  spine 
The  muscles  11,  12,  draw  the  scapula  upward  toward  the  head,  and  slightly  back- 
ward. The  muscle  4  draws  the  arm  by  the  side,  and  backward.  The  muscle  5 
elevates  the  arm.  The  muscles  8,  9,  extend  the  thigh  on  the  body.  The  muscle  1 
draws  the  head  back  and  elevates  the  chin.  The  muscle  16  depresses  the  ribs  <r 
expiration.  The  muscle  22  elevates  the  ribn  in  inspiration 


ANATOMY    OF    THE    MUSCLES.  ^3 

159.  The  diaphragm,  or  midriff,  is  the  muscular  division 
between  the  thorax  and  the  abdomen.  It  is  penetrated  by  the 
O3sophagus  on  its  way  to  the  stomach,  by  the  aorta  conveying 
blood  toward  the  lower  extremity,  and  by  the  ascending  vena 
cava,  or  vein,  on  its  way  to  the  heart. 

Fig.  42. 


Pig.  42.  A  representation  of  the  under,  or  abdominal  side  of  the  diaphragm 
I,  2,  3,  4,  The  portion  which  is  attached  to  the  margin  of  the  ribs.  8,  10,  The  two 
fleshy  pillars  of  the  diaphragm,  which  are  attached  to  the  third  and  fourth  lumbar 
rertebrae.  9,  The  spinal  column.  11,  The  opening  for  the  passage  of  the  aorta. 
12,  The  opening  for  the  oesophagus.  13,  The  opening  for  the  ascending  vena  cava, 
or  vein. 

Observation.  The  diaphragm  may  be  compared  to  an  in- 
ferted  basin,  its  bottom  being  turned  upward  into  the  thorax, 
while  its  edge  corresponds  with  the  outline  of  the  edges  of  the 
lower  ribs  and  sternum.  Its  concavity  is  directed  toward  the 
abdomen,  and  thus,  this  cavity  is  very  much  enlarged  at  the 
expense  of  that  of  the  chest,  which  is  diminished  to  an  equal 
extent. 

159.  Describe  the  diaphragm.  What  vessels  penetrate  this  muscular 
«eptum? 

7 


74  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

160.  "  The  motions  of  the  fingers  do  not  merely  result  from 
the  action  of  the  large  muscles  which  lie  on  the  fore-arm, 
Jiese  being  concerned  more  especially  in  the  stronger  action? 
of  the  hands.  The  finer  and  more  delicate  movements  of 
the  fingers  are  performed  by  small  muscles  situated  m  the 
palm  and  between  the  bones  of  the  hand,  and  by  whicn  thd 
fingers  are  expanded  and  moved  in  all  directions  with  wonder- 
ful rapidity." 

Fig.  43.  Fig.  44. 


Fig   43.    A  front  view  of  the  superficial  layer  of  muscles  of  the  fore-arm.    5,  Tin 
lexor  carpi  radialis  muscle.    6,  The   palmaris  longus  muscle.    7,  One  of  the  fasci- 


160.  Where  are  the  muscles  situated  that  effect  the  larger  movements  of  the 
nand  ?  That  perform  the  delicate  movements  of  the  fingers  ?  Give  the  use 
«*f  some  of  the  muscles  represented  by  fig  43.  Those  represented  by  fig.  44 


ANATOMY    OF    THE    MUSCLES.  7» 

culi  of  the  flexor  sublimis  digitorum  muscle,  (the  rest  of  the  mustle  is  seen  beneath 
the  tendons  of  the  palmaris  longus.)  8,  TJie  flexor  carpi  ulnaris  muscle.  9,  The 
palmar  fascia.  11,  The  abductor  pollicis  muscle.  12,  One  portion  of  the  flexoi 
orevis  pollicis  muscle.  13,  The  supinator  longus  muscle.  14,  The  extensor  ossia 
metacarpi,  and  extensor  primi  internodii  pollicis  muscles,  curving  around  the  lower 
oorder  of  the  fore-arm.  15,  The  anterior  portion  of  the  annular  ligament,  which 
oinds  the  tendons  in  their  places. 

Practical  Explanation.  The  muscles  5,  6, 8,  bend  the  wrist  on  the  bones  of  the  fore- 
arm. The  muscle  7  bends  the  second  range  of  finger-bones  on  the  first.  The  mus- 
cle 11  draws  the  thumb  from  the  fingers.  The  muscle  12  flexes  the  thumb.  The 
muscle  13  turns  the  palm  of  the  hand  upward.  The  muscles  8, 13,  14,  move  the 
hand  laterally. 

Fig.  44.  A  back  view  of  the  superficial  layer  of  muscles  of  the  fore-arm.  5,  The 
extensor  carpi  radialis  longior  muscle.  6,  The  extensor  carpi  radialis  brevior 
muscle.  7,  The  tendons  of  insertion  of  these  two  muscles.  8,  The  extensor  com- 
munis  digitorum  muscle.  9,  The  extensor  minimi  digiti  muscle.  10,  The  extensor 
carpi  ulnaris  muscle.  13,  The  extensor  ossis  metacarpi  and  extensor  primi  inter- 
nodii muscles,  lying  together.  14,  The  extensor  secundi  internodii  muscle;  its 
tendon  is  seen  crossing  the  two  tendons  of  the  extensor  carpi  radialis  longior  and 
brevior  muscles.  15,  The  posterior  annular  ligament.  The  tendons  of  the  common 
extensor  muscle  of  the  fingers  are  seen  on  the  back  of  the  hand,  and  their  mode  of 
distribution  on  the  back  of  the  fingers. 

Practical  Explanation.  The  muscles  5, 6, 10,  extend  the  wrist  on  the  fore-arm.  The 
muscle  8  extends  the  fingers.  The  muscle  9  extends  the  little  finger.  The  muscles 

13  extend  the  metacarpal  bone  of  the  thumb,  and  its  first  phalanx.    The  muscle 

14  extends  the  last  bone  of  the  thumb.    The    muscles  10,  13, 14,  move  the  hand 
laterally. 


76  ANATOMY     PHYSIOLOGY,   AJVD    HYGIENE. 

CHAPTER    IX. 

PHYSIOLOGY  OP  THE  MUSCLES. 

161.  THE  muscles  exercise  great  influence  upon  the  sys- 
tem.    It  is  by  their  contraction  that  we  are  enabled  to  pursue 
different  employments.     By  their  action  the  farmer  cultivates 
his  fields,  the  mechanic  wields  his  tools,  the  sportsman  pursues 
his  game,  the  orator  gives  utterance  to  his  thoughts,  the  lady 
sweeps  the  keys  of  the  piano,  and  the  young  are  whirled  in 
the  mazy  dance.     As  the  muscles  bear  so  intimate  a  relation 
to  the  pleasures  and  employments  of  man,  a  knowledge  of 
the  laws  by  which  their  action  is  governed,  and  the  conditions 
upon  which  their  health  depends,  should  be  possessed  by  all. 

162.  The    peculiar   characteristic   of    muscular   fibres   is 
contractility,  or  the  power  of  shortening  their  substance  on 
the  application  of  stimuli,  and  again  relaxing  when  the  stim- 
ulus is  withdrawn.     This  is  illustrated  in  the  most  common 
movements  of  life.     Call  into  action  the  muscles  that  elevate 
the  arm,  by  the  influence  of  the  will,  or  mind,  (the  common 
stimulus  of  the  muscles,)  and  the  hand  and  arm  are  raised  ; 
withdraw  this  influence  by  a  simple  effort  of  the  will,  and  the 
muscles,  before  rigid  and  tense,  become  relaxed  and  yielding. 

163.  The  contractile  effect  of  the  muscles,  in  producing  the 
varied  movements  of  the  system,  may  be  seen  in  the  bending 
of  the  elbow.     The  tendon  of  one  extremity  of  the  muscle  is 
attached  to  the  shoulder-bone,  which  acts  as  a  fixed  point ;  the 
tendon  of  the  other  extremity  is  attached  to  one  of  the  bones 

161 — 172.  Give  the  physiology  of  the  muscles.  161.  What  are  some  of  the 
influences  exerted  by  the  muscles  on  the  system  ?  162.  "What  is  peculiar 
to  muscular  ft  ores  ?  How  is  this  illustrated  ?  163.  Explain  how  the  move 
ments  of  the  system  are  effected  by  the  contraction  of  the  muscles. 


PHYSIOLOGY    OF    THE    MUSCLES.  "77 

of  the  fore-arm.  When  the  swell  of  the  muscle  contracts,  or 
shortens,  its  two  extremities  approach  nearer  each  other,  and 
by  the  approximation  of  the  terminal  extremities  of  the  mus- 
cle, the  joint  at  the  elbow  bends.  On  this  principle,  all  the 
joints  of  the  system  are  moved.  This  is  illustrated  by  fig.  45. 

Fig.  45. 


2 

Fig.  45.  A  representation  of  the  manner  in  which  all  of  the  joints  of  the  body  are 
moved.  1,  The  bone  of  the  arm  above  the  elbow.  2,  One  of  the  bones  below  the 
elbow.  3,  The  muscle  that  bends  the  elbow.  This  muscle  is  united,  by  a  tendon,  to 
the  bone  below  the  elbow,  (4 ;)  at  the  other  extremity,  to  the  bone  above  the  elbow, 
(5.)  6,  The  muscle  that  extends  the  elbow.  7,  Its  attachment  to  the  point  of  the 
elbow.  8,  A  weight  in  the  hand  to  be  raised.  The  central  part  of  the  muscle 
3  contracts,  and  its  two  ends  are  brought  nearer  together.  The  bones  below  the 
elbow  are  brought  to  the  lines  shown  by  9,  10,  11.  The  weight  is  raised  in  the 
direction  of  the  curved  line.  When  the  muscle  6  contracts,  the  muscle  3  relaxes 
and  the  fore-arm  is  extended. 

Experiments.  1st.  Clasp  the  arm  midway  between  the 
shoulder  and  elbow,  with  the  thumb  and  fingers  of  the 
opposite  hand.  When  the  arm  is  bent,  the  inside  muscle 
will  become  hard  and  prominent,  and  its  tendon  at  the  elbow 
rigid,  while  the  muscle  on  the  opposite  side  will  become 
flaccid.  Extend  the  arm  at  the  elbow,  and  the  outside  muscle 
will  swell  and  become  firm,  while  the  inside  muscle  and  its 
tendon  at  the  elbow  will  be  relaxed. 


Explain  fig.  45.     Give  experiment  1st. 
7  * 


^8  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

2d.  Clasp  the  fore-arm  about  three  inches  below  the 
elbow,  then  open  and  shut  the  fingers  rapidly,  and  the  swell- 
ing and  relaxation  of  the  muscles  on  the  opposite  sides  of  the 
arms,  alternating  with  each  other,  will  be  felt,  corresponding 
with  the  movement  of  the  fingers.  While  the  fingers  are 
bending,  the  inside  muscles  swell,  and  the  outside  ones  be- 
come flaccid  ;  and,  while  the  fingers  are  extending,  the  inside 
muscles  relax,  and  the  outside  ones  swell.  The  alternate 
swelling  and  relaxation  of  antagonist  muscles  ma^,  be  felt  in 
the  different  movements  of  the  limbs. 

164.  Each  fibre  of  the  several  muscles  receives  from  *he 
brain,  through  the  nervous  filament  appropriated  to  it,  a  cer- 
tain influence,  called  nervous  fluid,  or  stimulus.     It  is  this  that 
induces    contraction,  while  the   suspension   of  this  stimulus 
causes  relaxation  of  the  fibres.      By  this  arrangement,  the 
action  of  the   muscular  system,  both  as  regards  duration  and 
power,  is,  to  a  limited  extent,  under  the  control  of  the  mind. 
The  more  perfect  the  control,  the  better  the  education  of  the 
muscular  system ;  as  is  seen   in  the  graceful,  effective,  arid 
well-educated  movements  of  musicians,  dancers,  skaters,  &c. 

165.  The  length  of  time  which  a  muscle  may  remain  con- 
tracted, varies.     The  duration  of  the  contraction  of  the  volun- 
tary muscles,  in  some  measure,  is  in  an  inverse  ratio  to  its 
force.     If  a   muscle  has  contracted  with  violence,  as  when 
great  effort  is  made  to  raise  a  heavy  weight,  relaxation  will 
follow  sooner  than  when  the  contraction  has  been  less  power- 
ful, as  in  raising  light  bodies. 

166.  The  velocity  of  the  muscular  contraction  depends  on 
the  will.     Many  of  the  voluntary  muscles   in  man  contract 
with   great  rapidity,  so  that  he  is  enabled  to  utter  distinctly 

Give  experiment  2d.  104.  "With  what  is  each  muscular  fibre  supplied  ? 
What  effect  has  this  stimulus  on  the  muscles  ?  165.  How  long  does  a  vol- 
untary muscle  remain  contracted  ?  166.  On  what  is  the  velocity  of  mus- 
cular contraction  dependent  ?  How  many  letters  may  be  pronounced  in  a 
minute  ? 


PHYSIOLOGY    OF    THE    MUSCLES.  ^9 

fifteen  hundred  letters  in  a  minute ;  the  pronunciation  of  each 
letter  requiring  both  relaxation  and  contraction  of  the  same 
muscle,  thus  making  three  thousand  actions  in  one  minute. 
But  the  contraction  of  the  muscles  of  some  of  the  inferior 
animals  surpasses  in  rapidity  those  of  man.  The  race-horse, 
it  is  said,  has  run  a  mile  in  a  minute ;  and  many  birds  of  prey 
will  probably  pass  not  less  than  a  thousand  miles  daily. 

167.  The  functions  of  the  involuntary  muscles  are  neces- 
sary to  the  digestion  of  food,  the  absorption  and  circulation  of 
the  nutritive  fluids.     They  could  not  be  trusted  with  safety  to 
the  control  of  the  will,  lest  the  passions  or  the  indiscretions  of 
the  person  should  continually  avert  those  operations  so  neces- 
sary to  health,  and  even  to  life.     The  Divine  Builder  of  this 
complicated    machine    has  wisely  ordered  that  the   muscles 
upon  which  these  motions  depend,  shall  act  under  the  impres- 
sion  of  their  proper   stimulants,  without  the   control  of  the 
individual. 

168.  Again,  there  are  certain  operations  which  could  not 
be  safely  intrusted  to  the  absolute  government  of  the  voluntary 
muscles,  or  entirely  removed  from  their  control.     Thus  life 
can  be  supported  only  a  few  minutes  without  breathing ;  but 
it  would  be  impossible  to  perform  the  daily  vocations  of  life 
if  we  were  compelled  to  breathe  at  all  times,  or  at  perfectly 
regular  intervals. 

169.  It  has  been  observed  that,  among  men  of  the  same 
size,  a  wide  difference  exists    in  their  strength  and  activity 
—  qualities  which  depend  upon  the  size  and  number  of  the 
nerves,  the  size  and  activity  of  the  brain,  and  the  education, 
or  training  of  the  muscles.     Men  having  large  nerves  leading 

How  many  contractions  and  relaxations  of  the  same  muscle  ?  What  is 
said  of  the  rapidity  of  muscular  contractions  in  other  animals  ?  167.  When 
are  the  involuntary  muscles  called  into  action  ?  Why  would  it  not  have 
been  safe  to  trust  these  important  operations  to  the  exclusive  control  of  the 
will  ?  168.  Give  an  instance  where  some  of  the  muscles  act  under  the 
government  of  the  will,  conjoined  with  those  that  are  involuntary.  169.  Ou 
what  does  the  difference  in  muscular  activity  and  strength  depend  ? 


80  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

to  the  muscles,  with  the  brain  active,  and  muscles  well  trained 
will  perform  feats  of  strength  and  agility,  that  other  men,  of 
the  same  size,  cannot  effect.  Rope-dancers,  harlequins,  and 
other  performers  of  feats,  are  persons  thus  constituted. 

170.  Persons  with  small  muscles,  and  largely  developed 
nervous  systems,  will  sometimes  exhibit  very  great  muscular 
power  for  a  time;  but  it  will   not  be  of  long  continuance, 
unless   the    brain   is   functionally    diseased,   as   in   hysteria, 
delirium  of  fever,  insanity,  &c.     Men  of  large  muscles  and 
small  nerves  can  never  perform  feats  of  great  strength ;  but 
they  have  the  power  of  endurance,  and  are  better  capacitated 
for  continued  labor.     Thus  we  cannot  judge  of  the  ability  of 
persons  to  make  exertions  and  continue  them,  by  their  stature 
alone.     Strength,  and  the  power  of  endurance,  are  the  result 
of  a   combination   of  well-developed  muscles,  large  nerves, 
and  a  full-sized,  healthy,  and  active  brain. 

Observation.  The  muscles  of  fishes  are  large,  and  the 
aerves  distributed  to  them,  comparatively  small.  The  mus- 
cles of  birds  are  small,  but  their  fibres  are  very  compact. 
The  nerves  appropriated  to  the  muscles  that  are  called  into 
action  in  flying,  are  large  as  well  as  numerous. 

171.  The  contractile  portion  of  a  muscle  is,  in  general,  at 
a  distance  from  the  part  to  be  moved.     Thus  the  principal 
muscles  that  move  the  fingers  are  situated  upon  the  forearm, 
and  when  the   limb  is  nearly  or  quite  extended,   the  angle 
formed  by  the  part  to  be  moved  and  the  contractile  muscles 
is  small.     Again,  the  attachment  of  the  muscles  to  the  part 
to  be  moved  is  near  the  joint  that  forms  the  fulcrum,  (fig.  45.) 
By  these  arrangements  there  is  a  loss  of  power  ;  but  we  are 
compensated   for  this  disadvantage  by  increased  celerity  of 
movement,  beauty  of  form,  and  adaptation  of  the  limbs  to  the 
varied  pursuits  of  man. 

170.  What  is  said  of  those  persons  who  have  small  muscles  and  largely 
developed  nervous  systems  ?  Of  those  who  have  large  muscles  and  small 
nerves  ?  Upon  what  do  strength  and  the  power  of  endurance  depend  ? 
^71.  "WTby  is  there  a  loss  of  power  in  the  action  of  the  muscles  ? 


PHYSIOLOGY    OF    THE    MUSCLES.  8 

Illustration.  The  muscle  that  bends  the  elbow  acts  at 
disadvantage,  and  this  is  greatest  when  the  arm  is  nearly  or 
quite  extended,  as  the  angle  of  action  is  then  least.  This 
disadvantage  is  further  increased  by  the  attachment  of  the 
motive  muscles  near  the  joint. 

172.  The  number  of  muscles  which  are  called  into  action 
in  the  movements  of  the  different  joints,  varies.  The  hinge- 
joints,  as  the  elbow,  have  two  sets  of  muscles  —  one  to  bend 
the  joint,  the  other  to  extend  it.  The  ball  and  socket  joints , 
as  the  shoulder,  are  not  limited  to  mere  flexion  and  extension 
No  joint  in  the  system  has  the  range  of  movement  that  i$> 
possessed  by  that  of  the  shoulder.  By  the  action  of  the 
muscles  attached  to  the  arm,  it  is  not  only  carried  upward  and 
forward,  but  forward  and  backward.  Hence  the  arm  may  be 
moved  at  any  angle,  by  a  combined  action  of  its  muscles. 

Observation.  "  Could  we  behold  properly  the  muscular 
fibres  in  operation,  nothing,  as  a  mere  mechanical  exhibition, 
can  be  conceived  more  superb  than  the  intricate  and  combined 
actions  that  must  take  place  during  our  most  common  move- 
ments. Look  at  a  person  running  or  leaping,  or  watch  the 
motions  of  the  eye.  How  rapid,  how  delicate,  how  compli- 
cated, and  yet  how  accurate,  are  the  motions  required ! 
Think  of  the  endurance  of  such  a  muscle  as  the  heart,  that 
can  contract,  with  a  force  equal  to  sixty  pounds,  seventy-five 
times  every  minute,  for  eighty  years  together,  without  being 
weary." 

Note.  It  would  be  a  profitable  exercise  for  pupils  to  press  their 
fingers  upon  prominent  muscles,  and,  at  the  same  time,  vigorously 
contract  them,  not  only  to  learn  their  situations,  but  their  use;  as 
the  one  that  bends  the  arm,  14,  fig.  46. 


How  is  this  illustrated?  172.  Do  all  joints  require  the  same  number  of 
muscles,  when  called  into  action  ?  How  many  are  called  into  action  in  the 
movement  of  the  elbow?  What  is  their  office?  What  is  said  of  thf 
movement  of  the  ball  and  socket  joint  ? 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


PHYSIOLOGY    OF    Th£    MUSCLES. 
Fig.  47. 


<J4  ANATOMY     PHYSIOLOGY,    AND    HYGIENE. 

Fig.  46.  An  anterior  view  of  the  muscles  of  the  body.  1,  The  frontal  swell  of 
the  occipito-frontalis.  2,  The  orbicularis  palpebrarum.  3,  The  levatorlabii  superioris. 
4,  The  zygomaticus  major.  5,  The  zygomaticus  minor.  6,  The  masseter.  7,  The 
orbicularis  oris.  8,  The  depressor  labii  inferioris.  9.  The  platysma  myodes.  10,  The 
deltoid.  11,  The  pectoralis  major.  12,  The  latissimus  dorsi.  14,  The  biceps  flesor 
cubiti.  15,  The  triceps  extensor  cubiti.  16,  The  supinator  radii  longus.  18,  The 
flexor  carpi  radialis  longior.  19,  The  flexor  comrnunis  digitorum.  20,  The  annular 
ligament.  21,  The  palmar  fascia.  22,  The  obliquus  externus  abdominis.  26,  The 
psoas  magnus.  27,  The  adductor  longus.  28,  The  sartorius.  29,  The  rectua 
femoris.  30,  The  vastus  externus.  31,  The  vastus  internus.  32,  The  tendon  patella. 
33,  The  gastrocnemius.  34,  The  tibialis  anticus.  36,  The  tendons  of  the  extensor 
digitorum  communis. 

Fig.  47.  A  posterior  view  of  the  muscles  of  the  body.  3,  The  complexus.  4,  The 
splenius.  5,  The  masseter.  6,  The  sterno-cleido  mastoideus.  7,  The  trapeziua. 
8,  The  deltoid.  10,  The  triceps  extensor.  13,  The  tendinous  portion  of  the  triceps. 
14,  The  anterior  edge  of  the  triceps.  15,  The  supinator  radii  longus.  17,  The 
extensor  communis  digitorum.  18,  The  extensor  ossis  metacarpi  pollicis.  19,  The 
tendons  of  the  extensor  communis  digitorum.  20,  The  olecranon  process  of  the  ulna 
and  insertion  of  the  triceps.  21,  The  extensor  carpi  ulnaris.  22,  The  extensor  com- 
munis digitorum.  24,  The  latissimus  dorsi.  25,  Its  tendinous  origin  26,  The 
obliquus  externus.  27,  The  gluteus  medius.  28,  The  gJuteus  magnus.  29,  The 
biceps  flexor  cruris.  30,  The  semi-tendinosus.  31,32,  The  gastrocnemius.  33,  The 
tendo  Achillis. 

Practical  Explanation.  The  muscle  1,  fig.  46,  by  its  contraction,  raises  the  eyebrows. 
The  muscle  2,  fig.  46,  closes  the  eyelids.  The  muscle  3,  fig.  46,  elevates  the  upper  1m. 
The  muscles  4,  5,  fig.  46,  elevate  the  angles  of  the  mouth.  The  muscles  6,  fig.  4d, 
and  5,  fig.  47,  bring  the  teeth  together.  The  muscle  7,  fig.  46,  closes  the  mouth.  The 
muscle  8,  fig.  46,  depresses  the  lower  lip.  The  muscles  9,  fig.  46,  and  6,  fig  47,  bend 
the  neck  forward.  The  muscles  3,  4,  fig.  47,  elevate  the  head  and  chin.  The  muscle 
22,  fig.  46,  bends  the  body  forward,  and  draws  the  ribs  downward.  The  muscle  11, 
fig.  46,  brings  the  shoulder  forward.  The  muscle  7,  fig.  47,  draws  the  shoulder 
back.  The  muscles  10,  fig.  46,  and  8,  fig.  47,  elevate  the  arm.  The  muscles  11, 
fig.  46,  and  24,  fig.  47,  bring  the  arm  to  the  side.  The  muscle  14,  fig.  46,  bends 
the  arm  at  the  elbow.  The  muscle  10,  fig.  47,  extends  the  arm  at  the  elbow.  The 
muscles  16,  18,  fig.  46,  bend  the  wrist  and  fingers.  The  muscle  19  bends  the  fingers 
The  muscles  18,  21, 23,  fig.  47,  extend  the  wrist.  The  muscle  23,  fig.  47,  extends  the 
fingers.  The  muscles  26,  27,  28,  fig.  46,  bend  the  lower  limbs  on  the  body,  at  the  hip 
The  muscle  28,  fig.  46,  draws  one  leg  over  the  other,  (the  position  of  a  tailor  when 
sewing.)  The  muscles  27,  28,  fig  47  extend  the  lower  limbs  on  the  body,  at  the  hip 
The  muscles  29, 30, 31,  fig.  46,  extena  me  leg  at  the  knee.  The  muscles  29,  30,  fig.  47 
bend  the  leg  at  the  knee.  The  muscles  34,  36,  fig.  46,  bend  the  foot  at  the  ankle,  and 
sxtend  the  toes.  The  muscles  31,  32,  33,  fig.  47,  extend  the  foot  at  the  ankle. 

Note.  Let  the  anatomy  and  physiology  of  the  muscular  system  be  reviewed.,  m 
form  of  topics,  from  figs  46,  47,  or  from  the  anatomical  outline  plates  No.  3  and  4. 


HYGIENE  OF  THE  MUSCLES.  85 

CHAPTER     X. 

HYGIENE    OF    THE    MUSCLES 

173.  The  muscles  should  be  used,  in  order  that  the  size  and 
strength  of  these  organs  may  be  adequate  to  the  demand  made 
upon   them.     It  is  a  law  of  the  system  that  the  action  and 
power  of  an  organ  are  commensurate,  to  a  certain  extent,  with 
the  demand  made  upon  it ;  and  it  is  a  law  of  the  muscular 
system  that,  whenever  a  muscle  is  called  into  frequent  use,  its 
fibres  increase  in  thickness  within  certain  limits,  and  become 
capable  of  acting  with  greater  force  ;  while,  on  the  contrary, 
the  muscle  that  is  little  used  decreases  in  size  and  power. 

Illustrations.  1st.  The  blacksmith  uses  and  rests  the  mus- 
cles of  his  arm  when  striking  upon  the  anvil.  They  not  only 
increase  in  size,  but  become  very  firm  and  hard. 

2d.  The  student  uses  the  muscles  of  the  arm  but  little,  in 
holding  his  books  and  pen;  they  not  only  become  small, 
but  soft. 

3d.  Let  the  student  leave  his  books,  and  wield  an  iron 
sledge,  and  the  muscles  of  his  arm  will  increase  in  size  and 
firmness.  On  the  other  hand,  let  the  blacksmith  assume  the 
student's  vocation,  and  the  muscles  of  his  arm  will  become 
soft  and  less  firm. 

174.  When  the  muscles  are  called  into  action,  the  flow  of 
blood  in  the  arteries  and  vzins  is  increased.     The  increased 
flow  of  blood  in  the  arteries  and  veins,  causes  a  more  rapid 
deposition  of  the  particles  of  matter  of  which  the  muscles  are 

173 — 211.  G-ive  the  hygiene  of  the  muscles.  173.  What  is  necessary  that 
muscles  may  attain  size  and  strength  ?  Give  a  law  of  the  muscular  system. 
Show  this  by  practical  illustrations.  174.  Why  do  muscles  increase  in  size 
when  exercised  ? 

8 


86  ANATOMY,  PHYSIOLOGY,  AND  HYGIENE. 

composed.  If  the  exercise  is  adequate  to  the  power  of  the 
system,  the  deposit  of  new  material  will  exceed  in  quantity 
the  particles  of  matter  removed,  and  both  the  size  and  energy 
of  the  muscles  are  increased.  But  there  is  a  limit  to  the 
muscles  becoming  strong  by  labor.  Sooner  or  later,  man  will 
attain  his  growth  or  power ;  yet  by  judicious  exercise,  care, 
and  discreet  management,  the  greatest  power  of  the  muscles 
may  be  preserved  until  advanced  age. 

175.  The  muscles  are  lessened  in  size  and  diminished  in 
power  when  the  exercise  is  continued  so  as  to  produce  a  feel- 
ing of  exhaustion.     The  loss  of  material,  in  this  instance,  will 
exceed  the  deposition  of  the  atoms  of  matter.     This  is  seen 
in  the  attenuated  frames  of  over-tasked  domestic  animals,  as 
the  horse.     The    same  truth   is    illustrated  by  the  laborious 
agriculturist,  who,  in  consequence  of  too  severe  toil  while 
gathering  the  products  of  the  field,  frequently  diminishes  his 
weight  several   pounds  in  a  few  weeks.     Exercise,  either  for 
pleasure  or  profit,  may  fatigue,  yet  it  should  never  be  pro- 
tracted to  languor  or  exhaustion,  if  the  individual  desires  "  a 
green  old  age." 

176.  The  same  amount  of  exercise  will  not  conduce  to  the 
health   of  all  individuals.     If  riding  or   walking  one    mile 
causes  slight  fatigue,  this  may  be  beneficial  ;  while,  by  trav- 
elling two   miles,  the   exhaustion   may  be  highly   injurious. 
Exercise  and  labor  should  be  adapted  to  the  strength  of  par- 
ticular individuals.     How  little  soever  the  strength,  that  must 
be  the  measure  of  exertion.     Any  other  rule  would  be  fatal 
to  the  hopes  of  invigorating  the  system,  either  by  exercise 
or  labor. 


Is  there  a  limit  to  the  muscles  becoming  powerful  by  action  ?  How  may 
the  strength  of  muscles  be  kept  until  advanced  age  ?  175.  "What  is  the 
effect  when  exercise  is  continued  until  there  is  a  feeling  of  exhaustion  ? 
Give  a  practical  illustration.  What  rule  is  mentioned  in  regard  to  exer- 
cise ?  176.  Can  all  persons  take  the  same  amount  of  exercise  ?  What 
rule  is  given  as  to  the  amount  of  exercise  ? 


HYGIENE  OF  THE  MUSCLES.  87 


177.  Relaxation  must  follow  contraction,  or,  in  jther 

rest  must  follow  exercise.  The  necessity  of  relaxation,  when 
a  muscle  has  been  called  into  action,  is  seen  in  the  example 
of  a  boy  extending  his  arm  with  a  book  in  his  hand,  as  a 
penalty.  The  boy  can  keep  the  arm  extended  but  a  short 
time,  make  what  effort  he  may.  It  is  also  seen  in  the  rest- 
lessness and  feverish  excitement  that  are  evinced  by  per- 
sons gazing  on  troops  during  days  of  review.  The  same  is 
noted  in  shopping.  Such  employments  call  into  action  the 
muscles  that  support  the  spinal  column  in  an  erect  position, 
and  the  languor  or  uneasiness  is  muscular  pain.  The  long- 
continued  tension  of  a  muscle  enfeebles  its  action,  and  event 
ually  destroys  its  contractility. 

178.  In   school,  the  small  children,  after  sitting   a  short 
time,  become  restless.     If  their  position  be  changed,  their  im- 
perfectly developed  muscles  will  acquire  tone,  and  will  again 
support  the  spinal  column  erect  without  pain.     The  necessity 
for  frequent  recesses  in  school,  is  founded  on  the  organic  law 
of  muscular  action  alternating  with  rest.     The  younger  and 
feebler   pupils   are,  the    greater   the   necessity  for   frequent 
recesses.     We  would  not  have  the  teacher  think  that  one  half 
of  the  time  should  be  spent  in  recesses  ;  or  the  mother,  that 
her  daughter  is  going  to  school  to  play.     But  we  do  maintain 
that  recesses  should  be  given,  and  that  they  should  be  short 
and  frequent,  especially  for  small  and  feeble  scholars. 

179.  Exhaustion  is  the  inevitable  result  of  continued  mus- 
cular contraction.     For  example,  let  a  lady  ply  the  needle 
quickly  for  some  hours,  and  the  muscles  of  the   back  and 
right  arm  will  become  exhausted,  which  will  be  indicated  by 
a  sense  of  weariness  in  these  parts.     A  change   of  emplcy- 

177.  What  is  said  of  the  contraction  and  relaxation  of  the  muscles  ?  Give 
examples  of  the  necessity  of  relaxing  the  muscles.  178.  Why  should  not 
small  children  be  confined  in  one  position  for  a  long  time  ?  What  evils 
result  from  this  practice  ?  What  class  of  pupils  should  have  recesses  mosi 
frequently  179.  What  effect  has  continued  muscular  contraction  ? 


88  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

ment  and  position  calls  into  action  a  different  set  of  muscles, 
and  the  exhausted  organs  are  relieved. 

180.  Much  more  labor  will  be  accomplished  by  taking  time 
to  relax  the  exhausted  muscles,  or  by  so  changing  the  employ- 
ment as  to  bring  into  action  a  new  set  of  muscles  ;  the  wood- 
man thus  relieves  himself,  by  sawing  and  splitting  alternately. 
This  principle  applies  to  the  labor  of   he  horse  and  ox  ;  and 
it  is  also  applicable  to  all  kinds  of  employment.     With  the 
invalid  convalescing  from  fever,  relapses  result  from  inatten- 
tion to  these  laws.     When  a  patient  is  recovering  from  sick- 
ness, his    physician   should  take  care  that   his  exercise   be 
proper,  neither  too  much,  too  little,  nor  too  long  continued. 

181.  The  muscles  of  growing  youths  will  not  endure  so 
much  exercise  or  labor  as  those  of  mature  men.     In  youth  a 
portion  of  the   vital,   or   nervous  energy   of  the   system,  is 
expended  upon  the  growth  of  the  organs  of  the  body,  while 
in  the  individual  who  has  attained  his  growth,  this  expendi- 
ture is  not  demanded ;  consequently  severe  labor  or  exercise 
should  not  be  imposed  on  growing  children. 

Observation.  In  the  campaigns  of  Napoleon  Bonaparte, 
his  army  was  frequently  recruited  by  mere  boys.  He  com- 
plained to  the  French  government,  because  he  was  not  supplied 
with  men  of  mature  years,  as  the  youths  could  not  endure  the 
exertion  of  his  forced  marches. 

182.  The  muscles  should  be  gradually  called  into  action. 
These  organs  in  action  require  more  blood  and  nervous  fluid 
than  when  at  rest.     As  the  circulation  of  these  fluids  can  onlj 
be  increased  in  a  gradual  manner,  it  follows,  that,  when  the 
muscular  system  has  been  in  a  state  of  rest,  it  should  not  sud- 
denly be  called  into  vigorous  action.     On  arising  from  a  bed, 
lounge,  or  chair,  the  first  movements  of  the  limbs  should  be 
slow,  and  then  gradually  increased. 

Observation.     If  a  man  has  a  certain  amount  of  work  to 

180.  How  can  the  greatest  amount  of  labor  be  secured  \vith  the  least 
exhaustion  to  the  muscles?  181.  Why  .should  not  severe  labor  be  imposed 
on  growing  children  ?  182.  How  should  the  muscles  be  called  into  action  ? 


0- 

JUKI? 

HYGIENE    OF    THEWMUSCLES.  89 

Vgrr 

perform  in  nine  hours,  and  his  muscles  have  been  in  a  state 
of  rest,  he  will  do  it  with  less  fatigue  by  performing  half  the 
amount  of  the  labor  in  five  hours,  and  the  remainder  in  four 
hours.  The  same  principle  should  be  regarded  in  driving 
horses  and  other  beasts  of  burden. 

183.  The  muscles  should  be  rested  gradually,  when  they 
have  been  vigorously  used.    If  a  person  has  been  making  great 
muscular  exertion  in  cutting  wood,  or  any  other  employment, 
instead  of  sitting  down  to  rest,  he  should  continue  muscular 
action,  for  a  short  time,  by  some  moderate  labor  or  amusement. 

184.  If  the  system  has  been  heated  by  muscular  action,  and 
the  skin  is  covered  with  perspiration,  avoid  sitting  down  u  to 
cool "  in   a   current  of   air ;  rather,   put  on  more   clothir.'g, 
and  continue   to   exercise    moderately.     In    instances   when 
severe  action  of  the  muscles  has  been  enduied,  bathing  and 
rubbing  the  skin  of  the  limbs  and  joints  that  have  been  used, 
are    of  much   importance.      The    laboring   agriculturist   and 
industrious  mechanic,  by  reducing  to  practice  this  suggestion, 
would  thus  prevent  soreness  of  the  muscles,  and  stiffness  of 
the  joints. 

185.  The  muscles  should  be  abundantly  supplied  with  pure 
blood.     This  state  of  the  circulating  fluid  requires  a  healthy 
condition  of  the  digestive  apparatus,  and  that  the  skin  should 
be  kept  warm  by  proper  clothing,  clean  by  bathing,  and  be 
acted   upon   by  pure  air   and    good   light ;    the    movements 
of  the  ribs  and   diaphragm  should  be  unrestricted,  and  the 
lungs  should  have  ample  volume  and  be  supplied  with   pure 
air.     In  all  instances,  muscular  power  is  greatest  when  the 
preceding  conditions  exist,  as  the  muscles  are  then  stimulated 
by  pure  blood  ;  consequently,  it  is  of  practical  importance  to 

183.  How  should  the  muscles  be  rested  when  they  have  been  vigorously 
used  ?  184.  What  precaution  is  given  when  the  skin  is  covered  with  per- 
spiration ?  How  may  soreness  of  the  muscles,  consequent  upon  seve\e 
action,  be  prevented  ?  185.  Should  the  muscles  be  supplied  with  pure 
blood  ?  When  is  muscular  power  the  greatest  ? 
8* 


4  V 

90  ANATOMY,    PHYSIOLOGY,  AND    HYGIENE. 

the  mechanic,  the  farmer,  the  man  of  leisure,  and  not  less  so 
to  the  ladies,  to  observe  these  conditions,  whatever  vocation  of 
life  they  pursue. 

186.  The  muscles  should  be  used  in  pure  air.     The  purer 
the  air  we  breathe,  the  more  stimulating  the  blood  supplied  to 
the  muscles,  and  the  longer  they  can  be  used  in  labor,  walk- 
ing, or  sitting,  without  fatigue  and  injury ;  hence  the  benefit 
derived  in  thoroughly  ventilating  all  inhabited  rooms.     For  the 
same  reason,  if  the  air  of  the  sick-room  is  pure,  the  patient 
will  sit  up  longer  than  when  the  air  is  impure. 

Observation.  It  is  a  common  remark  that  sick  persons  will 
sit  up  longer  when  riding  in  a  carriage,  than  in  an  easy  chair 
in  the  room  where  they  have  lain  sick.  In  the  one  instance, 
they  breathe  pure  air;  in  the  other,  usually,  a  confined,  im- 
pure air. 

187.  The  muscles  should  be  exercised  in  the  light.     Light, 
particularly  that  of   the  sun,  exercises  more  or  less  influence 
on  man  and  the  inferior  animals  as  well  as  on  plants.    Both 
require  the  stimulus  of  this  agent.     Shops  occupied  by  me- 
chanics, kitchens,  and  sitting-rooms,  should  be  well  lighted, 
and  situated  on  the  sunny  side  of  the  house.     Cellar  kitchens 
and   underground   shops    should    be    avoided.      For   similar 
reasons,  students  should  take   their  exercise  during  the  day, 
rather  than  in  the  evening,  and,  as  much  as  possible,  laborers 
should  avoid  night  toil. 

Illustrations.  Plants  that  grow  in  the  shade,  as  under 
trees,  or  in  a  dark  cellar,  are  of  lighter  color  and  feebler 
than  those  that  are  exposed  to  the  light  of  the  sun.  Pe^ons 
that  dwell  in  dark  rooms  are  paler  and  less  vigorous  than 
those  who  inhabit  apartments  well  lighted,  and  exposed  to  the 
rays  of  the  sun. 

186.  Why  should  the  muscles  be  used  in  pure  air  ?  Give  a  common 
observation.  187-  What  effect  has  light  on  the  muscular  system  ?  What 
should  the  laborer  avoid  ?  Why  should  not  students  take  their  daily  exer- 
cise in  the  evening  ?  How  is  the  influence  of  solar  light  illustrated  ? 


HYGIENE    OF    THE    MUSCLES,  91 

188.  Exercise  should  ~be  regular  and  frequent.     The  sys 
tern  needs  this  means  of  invigoration  as  regularly  as  it  does 
new  supplies  of  food.     It  is  no  more  correct  that  we  devote 
several  days  to  a  proper  action  of  the  muscles,  and  then 
spend  one  day  inactively,  than  it  is  to  take  a  proper  amount 
of  food  for  several  days,  and  then  withdraw  this  supply  for 
a  day.     The   industrious  mechanic  and  the  studious  minister 
suffer  as  surely  from  undue  confinement  as  the  improvident 
and  indolent.     The  evil  consequences  of  neglect  of  exercise 
are  gradual,  and  steal  slowly  upon  an  individual.     But  sooner 
or  later  they  are  manifested  in  muscular  weakness,  dyspepsia, 
and  nervous  irritability. 

Observation.  The  custom  among  farmers  of  enduring 
severe  and  undue  toil  for  several  successive  days,  and  then 
spending  one  or  two  days  in  idleness  to  rest,  is  injudicious. 
It  would  be  far  better  to  do  less  in  a  day,  and  continue  the 
labor  through  the  period  devoted  to  idleness,  and  then  no  rest 
will  be  demanded. 

189.  Every  part  of  the  muscular  system  should  have  its 
appropriate  share  of  exercise.     Some  employments  call  into 
exercise  the  muscles  of  the  upper  limbs,  as  shoe-making ; 
others,  the  muscles  of  the  lower  limbs ;   while  some,  the  mus- 
cles of  both  upper  and  lower  limbs,  with  those  of  the  trunk, 
as  farming.     In  some  kinds  of  exercise,  the  lower  limbs  are 
mainly  used,  as  in  walking ;  in  others,  the  upper  limbs ;  and 
again,  the  muscles  of  the  trunk,  together  with  those  of  the 
upper  and  lower  limbs,  as  in  archery,  quoits,  playing  ball. 
Those  trades  and   kinds  of   exercise  are   most   salutary,  in 
which  all  the  muscles  have  their  due  proportion  of  action, 

188.  How  should  exercise  be  taken  ?  What  is  said  respecting  irregular 
exercise  ?  Are  the  consequences  of  neglected  exercise  immediately  appa- 
rent ?  What  practical  observation  is  given  ?  189.  Should  every  muscle 
have  its  due  amount  of  exercise  ?  Mention  some  employments  that  only 
pall  into  action  the  muscles  of  the  upper  limbs.  Those  of  the  lower  limbs, 
""•hose  of  the  trunk  and  limbs.  Mention,  in  the  different  pastimes,  whal 

mscles  are  called  into  action. 


92  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

as  this  tends  to  develop  and  strengthen  them  equally.  Thus 
labor  upon  the  farm  and  domestic  employment  are  superior 
as  vocations,  and  archery,  quoits,  and  dancing,  if  the  air  is 
pure,  among  the  pastimes.  For  sedentary  persons,  that  kind 
of  exercise  is  best  which  calls  into  action  the  greatest  number 
of  muscles. 

190.  The  proper  time  for  labor  or  exercise  should  be  ob- 
served.    This    is    modified  by  many  circumstances.     As  a 
general  rule,  the  morning,  when  the  air  is  pure  and  the  ground 
dry,  is  better  than  the  evening ;  for  then,  the  powers  of  the 
body  are   greatest.      Severe   exercise  and  labor    should   be 
avoided  immediately  before  or  after  eating  a  full  meal,  for 
the  energies  of  the  system  are  then  required  to  perform  the 
digestive  function.     For  similar  reasons,  it  is  not  an  appro- 
priate time  for  energetic  muscular  action  immediately  before 
or  after  severe  mental  toil,  as  the  powers  of  the  system  are 
then  concentrated  upon  the  brain.* 

191.  The  muscles  require  sleep  to  restore  their  expended, 
energies.     Among  the  arrangements  of  creative  wisdom,  no 
one  harmonizes  with  the  wants  of  the  system  more  than  the 
alternation  of  day  and  night.     The  natural  inclination  of  man 
to  sleep,  is  in  the  stilly  hour  of  night,  when  all  nature  reposes, 
and  to  be  in  action  during  the  light  of  day.     An  inversion  of 
this  law  of  rest  causes  greater  exhaustion  of  the  system  than 


*  It  appears  to  be  a  fact,  that  no  two  important  organs  can  be 
called  into  intense  action  at  the  same  time,  without  injury  to  both, 
as  well  as  to  the  general  system.  This  arises  from  the  circumstance 
that  an  organ,  when  in  functional  action,  attracts  fluids  (sanguineous 
and  nervous)  from  other  organs  of  the  system.  Except  in  a  few 
instances  of  high  health  in  youth,  the  power  of  the  system  is  not 
adequate  to  supply  more  than  one  organ  in  action  with  the  appro- 
priate fluids  at  the  same  time: 

What  kinds  of  exercise  are  best  ?  190.  What  rule  is  given  respecting 
the  time  for  exercise  ?  191.  Why  do  the  muscles  require  sleep  ?  What  w 
the  eifect  of  an  inversion  of  the  law  of  rest  ? 


HYGIENE    OF     THE    MUSCLES.  93 

the  same  amount  of  exertion  during  daylight.  This  is  illus- 
trated by  the  wearied  and  exhausted  condition  of  watcherst 
night-police,  and  other  individuals  who  spend  a  part  of  the 
night  in  some  active  business  of  life. 

192.  The  muscles  should  not  be  compressed.     Compression 
prevents  the  blood  from  passing  to  the  muscles  with  freedom ; 
consequently,  they  are  not  supplied  with  material  to  renovate 
and  promote  their  growth.     Again,  pressure  stimulates  the 
lymphatics  to  action ;  and  by  the  increased  activity  of  these 
vessels  the  muscles  are  attenuated.     In  the  case  of  a  man  with 
a  fractured  limb,  the  muscles  are  not  only  enfeebled  by  inac- 
tion, but  diminished  in  size  by  compression  from  the  dressing. 
Limbs  enfeebled  in  this  way  will  not  recover  their  size,  tone, 
and  strength,  until  the  bandages  are  removed,  and  a  proper 
amount  of  exercise  taken. 

193.  The  pressure  of  tight  dresses,  under  the  name  of  a 
"  snug  fit,"  enfeebles  the  muscles  of  the  back,  and  is  a  com- 
mon cause  of  projecting  shoulders  and  curvature  of  the  spinal 
column.     Thus  every  appendage   to  the  dress  of  ladies  which 
prevents  free  motion  of  the  muscles  of  the  chest  and  spinal 
column,  weakens  the   muscles  thus  restrained,  and  not  only 
prevents  the  proper  expansion  of  the  lungs,  but,  by  weakening 
the  muscles  which  sustain  the  spine,  induces  curvature  and 
disease.     Whalebone,  wood,  steel,  and  every  other  unyielding 
substance,  should  be  banished  from  the  toilet,  as  enemies  of 
the  human  race. 

194.  The  mind  exerts  a  great  influence  upon  the  tone  and 
contractile  energy  of  the  muscular  system.     A  person  acting 
under  a  healthy  mental  stimulus  will  make  exertion  with  less 
fatigue  than  he  would  without  this  incentive.     For  this  reason, 
a  sportsman  will  pursue  his  game  miles  without  fatigue,  while 

192.  Why  should  not  the  muscles  be  compressed  ?  193.  What  is  the 
effect  of  tight  clothing  upon  the  muscles  ?  194.  What  is  said  of  the  influ- 
ence of  the  mind  upon  muscular  activity  ?  Give  an  illustration  of  mental 
stimulus  cooperating  with  muscular  activity  in  the  case  of  a  sportsman. 


94  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

his  attendant,  not  having  any  mental  stimulus,  will  become 
weary.  Again,  if  the  sportsman  spends  some  hours  in 
pursuit  of  his  favorite  game  without  success,  a  feeling  of 
languor  creeps  over  him ;  but  while  he  is  thus  fatigued  and 
dispirited,  let  him  catch  a  glimpse  of  the  game,  —  his  wearied 
feelings  are  immediately  dissipated,  and  he  presses  on  with 
renewed  energy  and  recruited  strength. 

195.  This  principle  was  well  illustrated  in  the  retreat  from 
Russia  of  the  defeated  and  dispirited  French  army.     When  nc 
enemy  was  near,  they  had  hardly  strength  sufficient  to  carry 
their  arms  ;    but  no  sooner  did  they  hear  the  report  of  the 
Russian  guns,  than  new  life  seemed  to  pervade  them,  and  they 
wielded  their  weapons  powerfully  until  the  foe  was  repulsed , 
then  there  was  a  relapse  to  weakness,  and  prostration  followed. 
It  is  thus  with  the  invalid  when  riding  for  his  health ;  —  relate 
an  anecdote,  or  excite  this  mental  stimulus  by  agreeable  con- 
versation, and  much   benefit  will  accrue  from  the  ride  to  the 
debilitated  person.     So  it  is  in  the  daily  vocations  of  life  ;  if 
the  mind  have  some  incentive,  the  tiresomeness  of  labor  will 
be  greatly  diminished.     Let  an  air  of  cheerfulness  ever  per- 
vade our  every  employment,  and,  like  music,  "  it  sweetens 
toil." 

196.  Facts  illustrative  of  the  inutility  of  calling  the  muscles 
into  action,  without  the  cooperation  of  the  mind,  are  seen  in 
the  spiritless  aspect  of  many  of  our  boarding  school  proces- 
sions, when  a  walk  is  taken   merely  for  exercise,  without 
having   in  view  any  attainable    object.     But  present  to   the 
mind  a    botanical  or  geological  excursion,  and  the  saunter 
will  be  exchanged  for  the  elastic  step,  the  inanimate  appear- 
ance for  the  bright  eye  and  glowing  cheek.     The  difference 

195.  Give  an  illustration  of  mental  stimulus  cooperating  with  muscular 
activity  in  the  case  of  the  dispirited  French  army  in  their  retreat  from 
Russia.  How  can  a  union  of  mental  impulse  and  muscular  action  be  ben 
eficial  to  an  invalid  ?  Does  this  same  principle  apply  to  those  who  labor  ? 
196.  Give  an  instance  of  the  different  effects  produced  by  the  absence  and 
presence  of  the  mental  stimulus 


HYOriEJNE    OF    THE    MUSCLES.  95 

is,  simply,  that,  in  the  former  case,  the  muscles  are  obliged  to 
work  without  that  full  nervous  impulse  so  essential  to  their 
energetic  action  ;  and  that,  in  the  latter,  the  nervous  influence 
is  in  full  and  harmonious  operation. 

197.  It  must  not,  however,  be  supposed  that  a  walk  sim- 
|/ly  for  the  sake  of  exercise  can  never  be  beneficial.  Every 
one,  unless  prevented  by  disease,  should  consider  it  a  duty  to 
ake  exercise  every  day  in  the  open  air ;  if  possijble,  let  it  be 
had  in  combination  with  harmonious  mental  exhilaration ;  if 
not,  let  a  walk,  in  an  erect  position,  be  made  so  brisk  as  to 
produce  rapid  respiration  and  circulation  of  the  blood,  ar.d  in 
a  dress  that  shall  not  interfere  with  free  motions  of  +jie  arms 
and  free  expansion  of  the  chest. 

Observation.  The  advantages  of  combining  harmonious 
mental  excitement,  with  muscular  activity,  is  thi^  given  by 
Dr.  Armstrong  :  — 

"  In  whate'er  you  sweat, 

Indulge  your  taste.     Some  love  the  manly  toils, 
The  tennis  some,  and  some  the  graceful  dance ; 
Others,  more  hardy,  range  the  purple  heath 
Or  naked  stubble,  where,  from  field  to  field, 
The  sounding  covies  urge  their  lab'ring  flight, 
Eager  amid  the  rising  cloud  to  pour 
The  gun's  unerring  thunder ;  and  there  are 
Whom  still  the  mead  of  the  green  archer  charm. 
He  chooses  best  whose  labor  entertains 
His  vacant  fancy  most  •  the  toil  you  hate 
Fatiyues  you  soon,  and  scarce  improves  your  limbs" 


197.  May  not  a  walk,  simply  as  an  exercise,  be  beneficial?    What  i« 
preferred : 


96  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

CHAPTER     XI. 

HYGIENE  OF   THE    MUSCLES,  CONTINUED, 

198.  The  erect  attitude  lessens  the  exhaustion  of  the  muscles* 
A  person  whose  position  is  erect  will  stand  longer,  walk  further, 
and  perform  more  labor,  than  an  individual  whose  position  is 
stooping,  but  equal  in  all  other  respects.     The  manly  port  in 
an  erect  attitude,  depends  chiefly  upon  the  action  of  the  mus- 
cles of  the  back ;  and  it  follows  that  the  fewer  the  muscles  in 
a  state  of  tension,  the  less  the  draught  upon  the  nervous  sys- 
tem, and  the  less  its  exhaustion.     Another  advantage  which 
attends  the  erect  position  is,  the  trunk  and  head  are  balanced 
upon  the  bones  and  cartilages  of  the  spinal  column.     If  the 
body  slightly  incline  forward,  the  muscles  attached  to  the 
posterior  side  of  the  spine,  by  a  gentle  contraction,  will  bring 
it  to  the  perpendicular,  and  even  incline  it  backward.     This 
is  immediately  removed  by  a  slight  contraction  of  the  muscles 
upon  the  anterior  side  of  the  spinal  column. 

199.  In  the  erect  position,  there  is  a  constant  slight  oscil- 
'ation  of  the  body  backward  and  forward,  like  the  movement 
of  a  pendulum ;  while,  in  the  stooping  posture,  the  muscles 
on  the  posterior  side  of  the  spinal  column  are  kept  in  a  state 
of  continued  tension  and  contraction,  to  prevent  the  body  from 
falling  forward.     This  enfeebles  the  muscles  of  the  back,  and 
exhausts  the  nervous  energy,  while  the  erect  position  favors 
their  development  and  power,  because  there  is  an  alternate 
contraction  and  relaxation  of   the   muscles.     Again,  in  the 
stooping  position,  the  lower  limbs  are  curved  at  the  knee.    In 

198.  Why  will  a  person  who  stands  erect  walk  further,  and  perform  more 
Labor,  than  if  he  assumed  the  stooping  posture  ?  199.  Why  are  the  muscles 
of  the  back  so  soon  exhausted  in  the  stooping  position  ? 


HYGIENE    OF    THE    MUSCLES.  97 

this  attitude,  there  is  a  constant  tension  of  the  muscles  of  the 
lower  extremities,  which  produces  muscular  exhaustion. 


Fig.  48.  Fig.  49. 


Fig.  48.  1,  A  perpendicular  line  from  the  centre  of  the  feet  to  the  upper  extremity 
of  the  spinal  column,  where  the  head  rests.  2,  2,  2,  The  spinal  column,  with  its  three 
natural  curves.  Here  the  head  and  body  are  balanced  upon  the  spinal  column  and 
joints  of  the  lower  extremities,  so  that  the  muscles  are  not  kept  in  a  state  of  tension 
This  erect  position  of  the  body  and  head  is  always  accompanied  with  straight  lower 
limbs. 

Fig.  49.   1,  A  perpendicular  line  from  the   centre  of  the  feet.    2,  Represents  the 
unnatural  curved  spinal  column,  and  its  relative  position  to  the  perpendicular,  (L 
The  lower  limbs  are  curved  at  the  knee,  and  the  body  ia  stooping  forward.    While 
standing  in  this  position,  the  musclea  of  the  lower  limbs  and  back  are  in  continued 
tension,  which  exhausts  and  weakens  them. 

What  is  represented  by  figs.  48  and  49  ? 
O 


98  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

200.  When  it  is  necessary  to  call  into  action  a  part  of  the 
muscles  of  the  system   in  the   performance  of  any  duty,  as 
those  of  the  lower  limbs  in  walking,  if  the  muscles  of  other 
parts  are  in  a  state  of  inaction,  the  influence  of  the  nervous 
system  can  be  determined  in  an  undivided  manner  upon  those 
parts  of  the  lower  limbs  in  action  ;  hence  they  will  not  so  soon 
become  wearied  or  exhausted,  as  when  this  influence  is  divided 
between  a  greater  number  of  muscles.     In  performing  any 
labor,  as  in  speaking,  reading,  singing,  mowing,  sewing,  &c. 
there  will  be  less  exhaustion,  and  the   effort  can  be  longei 
maintained  in  the  erect  position  of  the  body  and  head,  than  in 
a  stooping  attitude. 

Experiment.  Hold  in  each  hand  a  pail  of  water  or  equal 
weights,  in  a  stooping  posture,  as  long  as  it  can  be  done 
without  much  suffering  and  injury.  Again,  when  the  mus- 
cular pain  has  ceased,  hold  the  same  pails  of  water,  for  the 
same  length  of  time,  in  an  erect  posture,  and  note  the  differ- 
ence in  the  fatigue  of  the  muscles. 

201.  If  the  stooping  posture  is  acquired  in  youth,  we  are 
quite  certain  of  seeing   the   deformed  shoulders  in  old   age. 
Hence  the  importance  of  duly  exercising  the  muscles  of  tho 
uack,  for  when  they  are  properly  developed,  the  child  can  and 
will  stand  erect.     In  this  attitude,  the  shoulders  will  be  thrown 
back,  and  the  chest  will  become  broad  and  full. 

202.  Pupils,  while  standing  during  recitations,  often  inad- 
vertently assume  the  attitude  represented  by  fig.  49,  and  it  is 
the  duty  of  teachers  to  correct  this  position  when  assumed. 
When  a  child  or  adult  has  contracted  a  habit  of  stooping,  and 
has  become  round-shouldered,  it  can  be  measurably,  and  gen- 
erally, wholly,  remedied  by  moderate  and  repeated  efforts  to 
bring  the  shoulders  back,  and  the  spinal  column  in  an  erect 

200.  What  suggestion  when  it  is  necessary  to  call  into  action  a  part  of 
the  muscular  system  ?  Give  the  experiment  that  illustrates  this  principle. 
201.  "Why  shouid  a  child  be  taught  to  stand  erect  ?  202.  How  can  round 
shoulders  acquired  by  aabit  be  remedied  ? 


HYGIENE    OF    THE    MUSCLES  99 

position.  T  his  deformity  can  and  should  be  remedied  in  OUT 
schools.  It  may  take  months  to  accomplish  the  desired  end, 
yet  it  can  be  done  as  well  under  the  direction  of  the  kind 
instructor,  as  under  the  stern,  military  drill  sergeant,  who  nevei 
fails  to  correct  this  deformity  among  his  raw  recruits. 

Fig.  50. 


Fig.  50.    A  proper  position  in  sitting. 

203.  The  child  should  be  taught  to  sit  erect  when  employed 
in  study  or  work.  This  attitude  favors  a  healthy  action  of  the 
Carious  organs  of  the  system,  and  conduces  to  beauty  and 
symmetry  of  fern?  Schc^is  aie  more  or  less  inclined  to  lean 
forward  and  place  the  elbow  on  the  table  or  desk,  for  support 

203.  Why  should  the  erect  attitude  be  assumed  in  sitting  ? 


100  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

and  this  is  often  done  when  their  seats  are  provided  with 
backs.  Where  there  is  a  predisposition  to  curvature  of  the 
spine,  no  position  is  more  unfavorable  or  more  productive  of 
deformities  than  this ;  for  it  is  usually  continued  in  one  direc- 
tion, and  the  apparent  deformity  it  induces  is  a  projection  of 
the  shoulders.  If  the  girl  is  so  feeble  that  she  cannot  sit 

Fig.  51. 


Fig.  51.    An  improper  position  in  sitting 

erect,  «e  represented  by  fig.  50,  let  her  stand  or  recline  on  a 
couch;  either  is  preferable  to  the  position  represented  by  fig. 
51.  In  furnishing  school-rooms,  care  should  be  taken  that 
the  desks  are  not  so  low  as  to  compel  the  pupils  to  lean 
forward  in  examining  their  books. 


HYGIENE  OF  THE  MUSCLES.  101 

204.  The  muscles,  when  exhausted-,  cannot  endure  continued 
effort.     When  the  energies  of  the  muscular  system  have  been 
expended  by  severe  and  long-continued  exercise,  or  the  brain 
and  nervous  system  prostrated  by  protracted  mental  effort,  the 
muscles  are  unfitted  to  maintain  the  body  erect  in  standing  or 
sitting  for  a  long  time,  as  the  nervous  system,  in  its  exhausted 
state,  cannot  supply  a  sufficient  amount  of  its  peculiar  influ- 
ence to  maintain  the  supporting  muscles  of  the  body  and  head 
in  a  state  of  contraction.     Hence,  a  child  or  adult,  when  much 
fatigued,  should  not  be  compelled  to  stand  or  sit  erect  in  one 
posture,  but   should  be  permitted   to  vary  the    position   fre- 
quently, as  this  rests  and  recruits  both  the  muscular  and  the 
nervous  system. 

205.  A  slight  relaxation  of  the  muscles  tends  to  prevent 
their   exhaustion.      In  walking,    dancing,   and    most   of  the 
mechanical  employments,  there  will  be  less  fatigue,  and  the 
movements  will   be    more  graceful,  when   the   muscles   are 
slightly  relaxed.     When  riding  in  cars  or  coaches,  the  system 
does  not  suffer  so  severely  from  the  jar  if  there  is  a  s4ight 
relaxation  of  the  muscles,  as  when  they  are  in  a  state  of  rigid 
contraction. 

Experiments.  Attempt  to  bow  with  the  muscles  of  the 
limbs  and  trunk  rigid,  and  there  will  be  a  stiff  bending  of  th«» 
body  only  at  the  hip-joint.  On  the  other  hand,  attempt  to  bow 
with  the  muscles  moderately  relaxed  ;  the  ankle,  the  knee, 
and  the  hip-joint  will  slightly  bend,  accompanied  with  an  easy 
and  graceful  curve  of  the  body. 

206.  The  muscles  when  relaxed,  together  with  the  yielding 
character  of  the  cartilage,  and  the  porous  structure  of  the  ends 
of  the  bones  that  form  a  joint,  diffuse  or  deaden  the  force  of 

204.  When  are  the  muscles  unfitted  to  maintain  the  system  erect  either 
in  standing  or  sitting  ?  What  is  necessary  when  this  condition  of  the 
system  exists  ?  205.  Why  should  the  muscular  system  be  slightly  relaxed 
in  walking,  &c.  ?  Give  illustrative  experiments.  206.  What  is  the  reason 
that  we  do  not  feel  the  jar  in  falling  from  a  moderate  height  ? 

9  * 


102  ANATOMY,    PHYbJOLOGY,    AND    HYGIENE. 

jars,  or  shocks,  in  stepping  suddenly  down  stairs,  or  in  fall 
ing  from  moderate  heights.  Hence,  in  jumping  or  falling 
from  a  carriage,  or  any  height,  the  shock  to  the  organs  of 
the  system  may  be  obviated  in  the  three  following  ways : 
1st.  Let  the  muscles  be  relaxed,  not  rigid.  2d.  Let  the 
limbs  be  bent  at  the  ankle,  knee,  and  hips  ;  the  head  should 
be  thrown  slightly  forward,  with  the  trunk  a  little  stooping. 
3d.  Fall  upon  the  toes,  not  the  heel. 

Experiments.  Stand  with  the  trunk  and  lower  limbs  firm, 
and  the  muscles  rigid ;  then  jump  a  few  inches  perpend ic 
ularly  to  the  floor,  and  fall  upon  the  heels.  Again,  slightly 
bend  the  limbs,  jump  a  few  inches,  and  fall  upon  the  toes,  and 
the  difference  in  the  force  of  the  shock,  to  the  brain  and  other 
organs,  will  be  readily  noticed. 

207.  The  muscles  require  to  be  educated,  or  trained.     The 
power  of  giving  different  intonations  in  reading,  speaking,  sing- 
ing, the  varied  and  rapid  executions  in  penmanship,  and  all 
mechanical  or  agricultural  employments,  depend,  in  a  measure, 
upon  the  education  of  the  muscles.     In  the  first  effort  of  mus- 
cular education,  the  contractions  of  the   muscular  fibres  are 
irregular  and  feeble,  as  may  be  seen  when  the  child  begins  to 
walk,  or  in  the  first  efforts  of  penmanship. 

208.  Repetition  of  muscular  action  is  necessary.   To  render 
the  action  of  the  muscles  complete  and  effective,  they  must 
be  called  into  action  repeatedly  and  at  proper  intervals.     This 
education  must  be  continued  until  not  only  each  muscle,  but 
every  fibre  of  the  muscle,  is  fully  under  the  control  of  the 
will.     In  this  way  persons  become  skilful  in  every  employ- 
ment.    In  training  the  muscles  for  effective  action,  it  is  very 
important  that  correct   movements   be  adopted  at  the  corn- 
How  is  this  shown  by  experiment  ?    207.  Upon  what  do  the  different 

intonations  of  sound  or  mechanical  employments  depend  ?  Why  are  the 
first  efforts  in  educating  the  muscles  indifferent  or  irregular  ?  208.  Why 
is  repetition  of  muscular  action  necessary  ?  Why  is  it  important  that 
coirect  movements  be  adopted  in  the  first  efforts  of  muscular  education  ? 


HYGIENE    OF    THE    MUSCLES. 


103 


mencement.     If  this  is  neglected,  the   motions  will  be  con- 
strained and  improper,  while  power  and  skill  will  be  lost. 

Illustration.  If  a  boy,  while  learning  to  mow,  is  allowed 
to  swing  his  scythe  in  a  stooping  position,  twisting  his  body  at 
every  sweep  of  the  scythe,  he  will  never  become  an  easy, 
efficient  mower.  Proper  instruction  is  as  necessary  in  many 
of  the  agricultural  branches  as  in  the  varied  mechanical 
employments. 


Fig.  52. 


Fig.  53. 


Fig.  52.    An  improper,  but  not  an  unusual  position,  when  writing. 
Fig.  53.    A  proper  position,  when  writing. 

209.  Good  penmanship  requires  properly  trained  muscles. 
To  a  deficient  analysis  of  the  movements  of  the  arm,  hand, 
and  fingers,  on  the  part  of  teachers  and  pupils  in  penman- 
ship, together  with  an  improper  position  in  sitting,  is  to  be 

How  is  this  illustrated?  209  Why  have  so  many  pupils  failed  in 
acquiring  good  penmanship  ? 


104  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

ascribed  the  great  want  of  success  in  acquiring  this  art.  The 
pen  should  be  held  loosely,  and  when  the  proper  position  is 
attained,  the  scholar  should  make  an  effort  to  imitate  some 
definite  copy  as  nearly  as  possible.  The  movements  of  the 
fingers,  hand,  and  arm,  necessary  to  accomplish  this,  should 
be  made  with  ease  and  rapidity,  striving,  at  each  effort,  to 
imitate  the  copy  more  nearly. 

210.  When  the  arm,  hand,  and  fingers  are  rigid,  the  large 
muscles,  that  bend  and  extend  these  parts,  are  called  into  too 
intense  action.     This  requires  of  the  small  muscles,  that  pro- 
duce the  lateral  movements,  which  are  essential  to  rapidity  in 
writing,  an  effort  which  they  cannot  make,  or  can  with   diffi- 
culty accomplish. 

Experiment.  Vigorously  extend  the  fingers  by  a  violent 
and  rigid  contraction  of  the  muscles  upon  the  lower  part  of 
the  arm,  and  the  lateral  movement  which  is  seen  in  their  sep- 
aration cannot  be  made.  But  gently  extend  the  fingers,  and 
their  oblique  movements  are  made  with  freedom. 

211.  An  individual  who  is  acquainted  with  the  laws  of 
health,  whose  muscles  are  well  trained,  will  perform  a  certain 
amount  of  labor  with  less  fatigue  and  waste  to  the  system, 
than  one  who  is  ignorant  of  the  principles  of  hygiene,  and 
whose  muscles  are  imperfectly  trained.     Hence  the  laboring 
poor  have  a  deep  interest  in  acquiring  a  knowledge  of  prac- 
tical physiology,  as  well  as  skill  in  their  trade  or  vocation.     It 
is  emphatically  true  to   those   who  earn  their  bread  by  the 
"  sweat  of  their  brow,"  that  "  knowledge  is  power." 

210.  What  is  said  of  the  lateral  and  oblique  movements  of  the  arm 
hand,  and  fingers  in  writing  ?  How  is  this  shown  by  experiment  ?  211  Why 
is  the  study  of  physiology  and  hygiene  of  utility  to  vJie  laborer  ? 


ANATOMY  OF  THE  TEETH.  105 


CHAPTER     XII. 

THE    TEETH. 

212.  THE    teeth,    in   composition,  nutrition,  and   growth,, 
are  different  from  other  bones  of  the  body.     They  vary  in 
number  at  different  periods  of  life,  and,  unlike  other  bones, 
they  are  exposed  to  the  immediate  action  of  atmospheric  air 
and  foreign  substances.     The  bones  of  the  system,  generally, 
when  fractured,  unite ;  but  there  is  never  a  permanent  union 
of  a  tooth  when  broken. 

ANATOMY  OF  THE  TEETH. 

213.  The  TEETH  are  attached  to  the  upper  and  lower  jaw- 
bone, by  means  of  bony  sockets,  called  al've-o-lar  processes. 
These  give  great  solidity  to  the  attachment  of  the  teeth,  and 
frequently  render   their  extraction  difficult.     The  gums,  by 
their  fibrous,  fleshy  structure,  serve  to    fix   the   teeth   more 
firmly  in  the  jaw. 

Observation.  When  a  permanent  tooth  is  extracted,  these 
uony  processes  are  gradually  absorbed,  so  that  in  advanced 
age  there  remains  only  the  jaw-bone  covered  by  the  lining 
membrane  of  the  gum.  This  accounts  for  the  narrow  jaw 
and  falling  in  of  the  lips  in  old  age.  Frequently,  a  piece  of 
the  alveolar  process  comes  out  with  the  tooth  when  extracted, 
and  the  dentist  has  then  the  credit  of  "  breaking  the  jaw." 

212.  What  is  said  of  the  teeth  ?  In  what  respect  do  they  differ  from  other 
bones  of  the  body  ?  213—218.  Give  the  anatomy  of  the  teeth.  213.  What 
confines  the  teeth  in  the  jaw-bone  ?  What  becomes  of  the  socket  when  a 
tooth  is  removed?  What  effect  has  this  absorption  upon  the  jaw  and 
lips  ? 


106  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

No  great  injury  results  from  the  removal  of  the  process  in  this 
manner. 

214.  The  teeth  are  formed  in  the  interior  of  the  jaws,  and 
within  dent'al  cap'sules,  (membranous  pouches,)  which  are 
enclosed  within  the  substance  of  the  bone,  and  present  in 
their  interior  a  fleshy  bud,  or  granule,  from  the  surface  of 
which  exudes  the  ivory,  or  the  bony  part  of  the  tooth.  In 
proportion  as  the  tooth  is  formed,  it  rises  in  the  socket,  which 
is  developed  simultaneously  with  the  tooth,  and  passes  through 
the  gum,  and  shows  itself  without. 

Fig.  54. 


Fig.  54.  1,  The  body  of  the  lower  jaw.  2,  Ramus,  or  branch  of  the  Jaw,  to  which 
the  muscles  that  move  it  are  attached.  3,  3,  The  processes  which  unite  the  lower 
jaw  with  the  head,  t,  The  middle  and  lateral  incisor  tooth  of  one  side.  &,  The 
bicuspid  teeth,  c,  The  cuspids,  or  eye  teeth,  m,  The  three  molar  teeth.  A,  shows 
the  relation  of  the  permanent  to  the  temporary  teeth. 

215.  The  first  set,  which  appears  in  infancy,  is  called 
tem'po-ra-ry,  or  milk  teeth.  They  are  twenty  in  number  ;  ten 
in  each  jaw.  Between  six  and  fourteen  years  of  age,  the  tem- 
porary teeth  are  removed,  and  the  second  set  appears,  called 
per'ma-Jient  teeth.  They  number  thirty-two,  sixteen  in  each 
jaw. 

214.  Where  and  how  are  the  teeth  formed  ?  Explain  fig.  54.  215.  What 
are  the  first  set  called  ?  How  many  in  each  jaw  ?  The  second  set  ?  How 
many  in  number  ? 

\ 


ANATOMY    OF    THE    TEETH. 


107 


216.  The  four  front  teeth  in  each  jaw  are  called  in-ci'sors, 
(cutting  teeth  ;)  the  next  tooth  in  each  side,  the  cus'pid,  (eye 
tooth  ;)  the  next  two,  bi-cus'pids,  (small  grinders  ;)  the  next 
two,  mo'lars,  (grinders.)  The  last  one  on  each  side  of  tho 
jaw  is  called  a  wisdom  tooth,  because  it  does  not  appear  until 
a  person  is  about  twenty  years  old.  The  incisors,  cuspids, 
and  bicuspids,  have  each  but  one  root.  The  molars  of  the 
jpper  jaw  have  three  roots,  while  those  of  the  lower  jaw  have- 
but  two. 

Fig.  55. 


Fig.  55.  The  permanent  teeth  of  the  upper  and  lower  jaw.  a,  b,  The  incise  rs. 
i,  The  cuspids,  d,  e,  The  bicuspids.  /,  §-,  The  molars,  (double  teeth.)  h,  The  wis- 
dom teeth 

Observation.  The  shape  of  the  teeth  in  different  species  of 
animals  is  adapted  to  the  kind  of  food  on  which  they  subsist. 
Those  animals  that  feed  exclusively  on  flesh,  as  the  lion,  have 
the  cuspids,  or  canine  teeth,  largely  developed,  and  the  molars 
have  sharp  cutting  points.  Those  animals  that  feed  on  grass 
ind  grain,  as  the  horse  and  the  sheep,  have  their  molar  teeth 

•nore  rounded   and  flat  on  the  crown.     The  human  teeth  are 

•«•.  ^ 

216.  Give  the  names  of  the  permanent  teeth.  What  teeth  have  but  one 
root,  or  "fang"?  How  many  roots  have  the  molars  of  the  upper  jaw? 
Of  the  lower  jaw  ?  What  is  said  of  the  shi~e  of  the  teeth  in  different 
species  of  animals  ? 


108  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

adapted  to  feed  on  fruits,  grain,  or  flesh,  as  they  are  less 
pointed  than  those  of  the  cat,  and  more  pointed  than  those  of 
the  sheep. 

211  The  teeth  are  composed  principally  of  two  substances 
—  the  i'vo-ry  and  the  en-am1  el.  The  internal  part  of  the  tooth 
or  the  ivory,  is  harder  and  more  enduring  than  bone,  and  forms 
the  body  of  the  tooth.  The  enamel  is  remarkable  for  its  hard- 
ness, and  varies  somewhat  in  color  with  the  age,  temperament, 
habits,  and  manner  of  living  of  different  individuals.  When 
any  part  of  the  enamel  is  destroyed,  it  is  never  regenerated. 

Fig.  56.  Fig.  57. 


*ig  56.    A  side  view  of  the  body  aiyl  enamel  of  a  front  tooth. 

Fig  57.  A  side  view  of  a  molar  tooth.  1,  The  enamel.  2,  The  body  of  the  tooth 
3  The  cavity  in  the  crown  of  the  tooth  that  contains  tlie  pulp.  4,  A  nerve  thai 
spreads  in  the  pulp  of  the  tooth.  5,  An  artery  that  ramifies  in  the  pulp  of  the  tooth. 

218.  Each  tooth  is  divided  into  two  parts,  namely,  crown 
and  root.  The  crown  is  that  part  which  protrudes  from  the 
jaw-bone  and  gum,  and  is  covered  by  the  highly  polished 
enamel.  The  root,  or  "  fang,"  is  placed  in  the  sockets  of  the 
jaw,  and  consists  of  bony  matter.  Through  this  bony  sub- 
stance several  small  vessels  pass,  to  aid  in  the  growth  and 

217.  Give  the  structure  of  the  teeth.  What  is  said  of  the  enamel  ? 
218.  Into  how  many  parts  are  the  teeth  divided  ?  Describe  the  crown.  The 
root.  What  vessels  pass  through  the  bony  matter  ?  What  is  their  use  ? 


PHYSIOLOGY    OF    THE    TEETH.  109 

also  in  the  removal  of  the  tooth.  There  are,  beside  the»e 
vessels,  small  white  cords  passing  to  each  tooth,  called  nerves. 
(See  fig.  57.)  When  these  nerves  are  diseased,  we  have  the 
toothache. 

PHYSIOLOGY    OF    THE    TEETH. 

219.  The  use  of  the   teeth  is  twofold.     1st.  By  the  action 
of  the  incisors  the  food  is  divided,  while  the  molars  grind  or 
break  down  the  more  solid  portions  of  it.    By  these  processes, 
the  food  is  prepared  to  pass  more  easily  and  rapidly  into  the 
stomach. 

220.  In  the  mastication  of  food  there  are  two  movements 
of  the  lower  jaw  —  the  action  by  which  the  teeth  are  brought 
together,  and  the  lateral  motion.     In  the  former,  the  food  is 
cut  or  divided,  the  jaws  acting  like  shears.     This  movement 
is  produced  by  the  action  of  two  large  muscles  situated  on 
each  side  of  the  head  and  face. 

Observation.  The  muscles  attached  to  the  lower  jaw  are  of 
great  strength  ;  by  their  action  alone,  some  persons  are  ena- 
bled to  bite  the  hardest  substances.  By  putting  the  fingers 
upon  the  side  of  the  head  above  and  in  front  of  the  ears,  and 
upon  the  face  above  the  angle  of  the  jaw,  while  masticating 
food,  the  alternate  swelling  and  relaxation  of  these  muscles 
will  be  clearly  felt. 

221.  The  lateral,  or  grinding  movement  of  the  teeth,  is  pro- 
duced by  the  action  of  a  strong  muscle  that  is  attached  to  the 
tower  jaw  on  the  inside. 

Observation.  Those  animals  that  live  solely  on  flesh,  have 
only  the  cutting,  or  shear-like  movement  of  the  jaws.  Those 

219—222.  Give  the  physiology  of  the  teeth.  219.  Give  one  of  the  functions 
of  the  teeth.  220.  How  many  movements  of  the  lower  jaw  in  masticating 
food  ?  What  effect  has  the  first  movement  upon  the  food  ?  How  pro- 
duced ?  What  is  the  character  of  the  masticating  muscles  ?  221.  How  ia 
the  grinding  motion  of  the  teeth  produced  ?  What  is  said  of  the  move- 
ments of  the  teeth  in  different  animals  ? 
10 


110  ANATOMY,    PHYSIOL.OGY,    AND    HYGIENE. 

that  use  vegetables  for  food,  have  the  grinding  motion ;  while 
man  has  both  the  cutting -and  grinding  movement. 

222.  2d.  The  teeth  aid  us  in  articulating  with  distinctness 
certain  letters  and  words.     An   individual  who  has  lost  his 
front  teeth  cannot  enunciate  distinctly  certain  letters  called 
dental.     Again,  as  the  alveolar  processes  are  removed   by 
absorption  soon  after  the  removal  of  the  teeth,  the  lips  and 
cheeks  do  not  retain  their  former  full  position,  thus  marring,  in 
no  slight  degree,  the  symmetry  of  the  lower  part  of  the  face. 
Consequently,   those    simple    observances   that   tend   to   the 
preservation  of  the  teeth  are  of  great  practical  interest  to  all 
persons. 

HYGIENE    OF    THE    TEETH. 

223.  To  preserve  the  teeth,  they  must  be  kept  clean.     After 
eating  food,  they  should  be  cleansed  with  a  brush  and  water, 
or  rubbed  with  a  piece  of  soft  flannel,  to  prevent  the  tartar 
collecting,  and  to  remove  the  pieces  of  food  that  may  have 
lodged  between  them.     Toothpicks  may  be  useful   in  remov- 
ing any  particles  inaccessible  to  the  brush.     They  may  be 
made   of  bone,  ivory,  or  the  common  goose-quill.     Metallic 
toothpicks  should  not  be  used,  as  they  injure  the  enamel. 

224.  The  mouth  should  be  cleansed  with  pure  tepid  water  at 
night,  as  well  as  in  the  morning ;  after  which  the  teeth  should 
be  brushed  upward  and  downward,  both  on  the  posterior  and 
anterior  surfaces.     It  may  be  beneficial  to  use  refined  soap, 
once  or  twice  every  week,  to  remove  any  corroding  substance 
that  may  exist  around  the  teeth  ;   care  being  taken  to  thor- 
oughly rinse  the  mouth  after  its  use. 

225.  Food   or  drink  should  not  be  taken  into  the  mouth 
when  very  hot  or  very  cold.     Sudden  changes  of  temperature 
will  crack  the  enamel,  and  finally  produce  decayed  teeth. 

222.  What  is  another  use  of  the  teeth?  223—232.  Give  the  hygiene 
of  the  teeth.  223.  How  can  the  teeth  be  preserved  ?  By  what  means  ? 
224.  How  often  should  they  be  cleansed  ?  225.  "What  is  said  of  very  hot 
or  cold  drinks  ? 


HYGIENE  OF  THE  TEETH.  Ill 

Observation.  On  this  account,  smoking  is  pernicious,  be- 
cause the  teeth  are  subjected  to  an  alternate  inhalation  of  both 
cold  and  warm  air. 

226.  Tlie  temporary  teeth  should  be  removed  as  soon  as 
they  become  loose.     If  a   permanent  tooth  makes  it  appear- 
ance before  the  first  is  removed,  or  has  become  loose,  the 
rnilk  tooth,  although  not  loose,  should  be  removed  without 
delay.     This  is  necessary  that  the  second  set  of  teeth  may 
present  a  regular  and  beautiful  appearance. 

227.  In  general,  when  the  permanent  teeth  are  irregular, 
one  or  more  should  be  removed.     If  the  teeth  are  crowded  and 
irregular,  in  consequence  of  the  jaw  being  narrow  and  short, 
or  when  they  press  so  hard  upon  each  other  as  to  injure  the 
enamel,  remove  one  or  more  to  prevent  their  looking  unsight- 
ly, and  in  a  few  months  the  remaining  teeth,  with  a  little  care, 
will  fill  the  spaces. 

Observation.  When  it  is  necessary  to  remove  a  tooth,  apply 
to  some  skilful  operator.  It  requires  as  much  skill  and  knowl- 
edge to  extract  teeth  well,  as  it  does  to  amputate  a  limb  ;  yet 
some  persons,  who  possess  strong  arms,  will  obtain  a  pair  of 
forceps,  or  a  tooth-key,  and  hang  out  the  sign  of  "  surgeon- 
dentist,"  although  ignorant  of  the  principles  that  should  guide 
them. 

228.  It  is  not  always  necessary  to  have  teeth  extracted  when 
they  ache.      The  nerve,  or  the  investing  membrane  of  the 
root,  may  be  diseased,  and  the  tooth  still  be  sound.     In  such 
instances,  the  tooth  should  not  be  extracted,  but  the  diseased 
condition  may  be  remedied  by  proper  medication.     There  are 
many  sound  teeth,  that  become  painful,  as  already  mentioned, 
which  are  unnecessarily  removed. 


Why  is  smoking  injurious  to  the  teeth  ?  226.  "What  remark  respecting 
the  temporary  teeth?  227.  "What  remarks  respecting  the  permanent 
teeth?  Do  those  peisons  that  extract  teeth  require  skill  as  well  as  knowl- 
edge ?  228.  Why  should  not  teeth  be  extracted  at  all  times  when  they 
are  painful  ? 


112  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

Illustration.  Dr.  H.  M.,  of  Belfast,  Me.,  related  to  me  that 
an  individual  in  that  vicinity  had  his  teeth,  (all  of  them 
sound,)  on  one  side  of  the  lower  jaw,  extracted  by  an  igno- 
ramus of  a  "  tooth-puller,"  and  this  without  any  relief  from 
pain.  The  disease  was  tic  douloureux,  which  was  relieved 
by  Dr.  M. 

229.  The  preservation  of  the  teeth  requires  that  they  be 
frequently  examined.     When  a  part  of  the  enamel  is  removed, 
and  a  small  portion  of  the  body  of  the  tooth  has  become  cari- 
ous, in  many  instances  such  teeth  may  be   preserved  from 
further  decay  by  having  them  Jilled  or  "  plugged  "  with  gold 
foil.     All   amalgams,  pastes,  and  cheap   patent  articles  for 
filling,  should  be  avoided,  if  you  would  preserve  both  the  teeth 
and  the  general  health. 

230.  The  practice  of  cracking  nuts  with  the  teeth,  or  01 
lifting  heavy  bodies,  and  the  constant  habit  of  biting  thread, 
should  be  avoided,  as  they  finally  destroy  the  enamel. 

231.  All  acidulated  drinks  and  mineral  waters,  that  "  set 
the   teeth  on  edge"  are  injurious.     All   tooth-powders  and 
washes  that  contain  any  article  that  is  acid,  corrosive,  or  grind- 
ing, should  be  banished  from  the  toilet.    Tobacco  is  not  a  pre- 
servative of  the  teeth.     It  contains  "  grit,"  which  wears  away 
the  enamel ;  beside,  when  chewed,  it  debilitates  the  vessels  of 
the  gums,  turns  the  teeth  yellow,  and  renders  the  breath  and 
the  appearance  of  the  mouth  disagreeable. 

232.  Healthy  persons  have   generally  sound  teeth,  while 
feeble  persons  have  decayed  teeth.    For  this  reason,  we  should 
try  to  learn  and  practise  the  few  simple  rules  that  promote 
health. 


Give  an  illustration  of  the  removal  of  sound  teeth.  229.  How  may 
decaying  teeth  be  preserved  ?  What  should  be  avoided  in  the  filling  of 
teeth  ?  230.  What  practices  should  also  be  avoided  ?  231.  What  is  said 
of  acidulated  drinks  ?  What  effect  has  tne  chewing  of  tooacco  upon  the 
teeth  ?  232.  What  is  one  reason  for  preserving  health  ? 


ANATOMY    OF    THE    DIGESTIVE    ORGANS.  113 

CHAPTER    XIII. 

THE    DIGESTIVE    ORGANS. 

233.  FROM  the  earliest  existence  of  the  human  system  to 
the  last  ray  of  life,  change  is  impressed  upon  it  by  the  Giver 
of  this  curious  fabric.     New  atoms  of  matter  are  deposited, 
while    the    old   and    now   useless    particles    are    constantly 
removed.     The  *  material    necessary  to    sustain    the    growth 
of  the  body  in  early  life,  and  also  to  repair  the  waste  thai 
is  unceasing  to  animal  existence,  is  the  food  we  eat. 

234.  Food,  animal  or  vegetable,  contains  most  of  the  ele- 
ments of  the  different  tissues  of  the  system,  yet  it  must  un- 
dergo certain  essential  alterations  before  it  can  become  a  part 
of  the  body.     The  first  change  is  effected  by  the  action  of 
the  Digestive  Organs. 

ANATOMY  OF  THE  DIGESTIVE  ORGANS 

235.  The  DIGESTIVE  ORGANS  are  the  Mouth,  Teeth*  Sal'i 
va-ry   Glands,  Phar'ynx,   (E-soph'a-gus,    (gullet,)    Stom'ach, 
In-tes1  tines,    (bowels,)    Lac'te-als,    (milk,  or   chyle  vessels,) 
Tho-rac'ic  Duct,  Liv'er,  and   the  Pan'cre-as,    (sweetbread.) 

236.  The  MOUTH  is  an  irregular  cavity,  which  contains  the 
instruments  of  mastication   and   the    organs  of  tasie.     It  is 


*  See  Chapter  XII. 


233.  What  is  impressed  upon  the  human  system  from  its  earliest  exist- 
ence ?  What  maintains  this  change  ?  234.  Has  animal  or  vegetable  food 
any  resemblance  to  the  different  tissues  of  which  it  finally  forms  a  part } 
By  what  organs  is  the  first  change  in  the  food  effected  ?  235 — 268.  Give 
the  anatomy  qf  the  digestive  organs.  235.  Name  them.  236.  Describe  the 
mouth. 

10* 


114 


ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 


bounded  in  front  by  the  lips ;  on  each  side  by  the  internal 
surface  of  the  cheeks  ;  above,  by  the  hard  palate  (roof  of  the 
mouth)  and  teeth  of  the  upper  jaw  ;  below,  by  the  tongue  and 
teeth  of  the  lower  jaw  ;  behind,  it  is  continuous  with  the 
pharynx,  but  is  separated  from  it  by  a  kind  of  movable 
curtain,  called  the  soft  palate.  This  may  be  elevated  or 
depressed,  so  as  to  close  the  passage  or  leave  it  free. 

237.  The  SALIVARY  GLANDS  are  six  in  number;  three  on 
each  side  of  the  jaw.  They  are  called  the  pa-rot'id,  the 
sub-max'il'la-r'n .  and  the  sub-lin'gual. 

Fig.  58. 


Pig.  58.  A  view  of  the  salivary  glands  in  their  proper  situations.  1,  The  parotid 
gland.  2,  Its  duct.  3,  The  submaxillary  gland.  4,  Its  duct.  5,  The  sublinguol 
gland,  brought  to  view  by  the  removal  of  a  section  of  the  lower  jaw. 

238.  The  PAROTID  GLAND,  the  largest,  is  situated  in  front 
of  the  external  ear,  and  behind  the  angle  of  the  jaw.  A 
duct.  (Steno's)  from  this  gland  opens  into  the  mouth,  opposite 
the  second  molar  tooth  of  the  upper  jaw. 

237.  How  many  glands  about  the  mouth?  Give  their  names.  What 
does  fig.  5S  represent  ?  238.  Describe  the  parotid  gland. 


ANATOMY    OF    THE    DIGESTIVE    ORGANS. 


115 


239.  The  SUBMAXILLARY  GLAND-  is  situated  within  the  lowei 
jaw,  anterior  to  its  angle.     Its  excretory  duct  (Wharton's) 
opens  into  the   mouth  by  the  side   of  the  fra'num  lingua, 
(bridle  of  the  tongue.) 

240.  The  SUBLINGUAL  GLAND  is  elongated  and  flattened, 
and  situated  beneath  the   mucous  membrane  of  the  floor  of 

he  mouth,  on  each  side  of  the  frsenum  linguae.  It  has  seven 
or  eight  small  ducts,  which  open  into  the  mouth  by  the  side 
of  the  bridle  of  the  tongue. 

Observation.  In  the  "mumps,"  the  parotid  gland  la 
diseased.  The  swelling  under  the  tongue  called  the  "frog" 
ie  a  disease  of  the  sublingual  gland. 

Fig.  59. 


Pig  59.  A  side  view  of  the  face,  oesophagus,  and  trachea.  1,  The  trachea  (wind 
pipe.)  2,  The  larynx.  3,  The  oesophagus.  4,  4, 4,  The  muscles  of  the  upper  portion 
of  the  oesophagus,  forming  the  pharynx.  5,  The  muscle  of  the  cheek.  6,  The  mus- 
cle that  surround^  the  mouth.  7,  The  muscle  that  forms  the  floor  of  the  mouth. 

241.    The  PHARYNX  is  a  membranous  sac,  situated  upon  the 

239.  The  submaxillary.  240.  The  sublingual.  What  observation  respect- 
ing these  glands  ?  What  does  fig.  59  represent  ? 


/16  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

upper  portion  of  the  spinal  column.  It  extends  from  the  base 
of  the  skull  to  the  top  of  the  tra'che-a,  (windpipe,)  and  is 
continuous  with  the  oasophagus.  From  the  pharynx  are  foui 
passages  ;  one  opens  upward  and  forward  to  the  nose,  the 
second  leads  forward  to  the  mouth,  the  third  downward  to  the 
trachea  and  lungs,  the  fourth  downward  and  backward  to  the 
stomach. 

242.  The    OESOPHAGUS  is  a  large   membranous  tube  that 
extends  behind  the  trachea,  the    heart,  and    lungs,    pierces 
the  diaphragm,  and  terminates  in  the  stomach.     It  is  com- 
posed of   two  membranes  —  an  internal,  or  mucous,  and   a 
muscular  coat.     The  latter  is  composed  of  two  sets  of  fibres ; 
one   extends   lengthwise,  the    other   is   arranged  in  circular 
bands. 

243.  The  STOMACH  is  situated  in  the  left  side  of  the  abdo- 
men, immediately  below  and  in  contact  with  the  diaphragm. 
It  has  two   openings;    one   connected  with   the    oesophagus, 
called   the    car'di-ac   orifice ;   the  other   connected  with  the 
upper   portion   of   the   small   intestine,   called   the  py-lor'ic 
orifice.     It  is  composed  of  three  coats,  or  membranes.     The 
exterior  or  serous  coat    is  very  tough  and  strong,  and  in- 
vests every  part  of  this  important  organ.     The  middle,  or 
muscular  coat  is  composed  of  two  layers  of  muscular  fibres, 
one  set  of  which  is  arranged  longitudinally,  the  otner  circu- 
larly.   The  interior  coat  is  called  the  mucous,  and  is  arranged 
in  ru'gce,  (folds.)     The  stomach  is  provided  with  a  multitude 
of  small  glands,  in  which  is  secreted  the  gastric  fluid. 

Illustration.  The  three  coats  of  the  stomach  anatomically 
resemble  tripe,  which  is  a  preparation  of  the  largest  stomach  of 
the  cow  or  ox.  The  outer  coat  is  smooth  and  highly  polished. 
The  middle  coat  is  composed  of  minute  threads,  which  are 

241.  Describe  the  pharynx  and  the  passages  leading  from  it.  242.  Give 
the  structure  of  the  resophagus.  243.  Where  is  the  stomach  situated? 
How  many  coats  has  it,  ?  Describe  them.  "What  article  prepared  for 
food  does  the  stomach  resemble  ? 


ANATOMY    OF    THE    DIGESTIVE    ORGANS.  117 

an  inged  in  two  layers.  The  fibres  of  these  layers  ci  oss  each 
otner.  The  inner  coat  is  soft,  and  presents  many  folds,  usually 
OK  .i<s<i  "  the  honey-comb." 


Fig.  60.  T  ne  inner  surface  of  th*.  stomach  and  duodenum.  1,  The  lower  portior 
of  the  (esophagus.  2,  The  opening  through  which  the  food  is  passed  into  the  stomach. 
8,  The  stomach.  9,  The  opening  through  wiiich  the  food  passes  out  of  the  stomach 
Into  the  duodenum,  or  upper  portion  of  the  small  intestine.  10, 11, 14,  The  duodenum. 
12, 13,  Ducts  through  which  the  bile  and  pancreatic  fluid  pass  into  it.  o,  b,  c,  The 
three  coats  of  the  stomach. 

244.  The  INTESTINES,  or  alimentary  canal,  are  divided  into 
two  parts  —  the  small  and  large.  The  small  intestine  is  about 
twenty-five  feet  in  length,  and  is  divided  into  three  portions, 
namely,   the  Du-o-de'num,   the  Je-ju'num,    and    the  Il'e-um. 
The  large  intestine  is  about  five  feet  in  length,  and  is  divided 
into  three   parts,  namely,  the   Cce'cum,  the  Co'lon,  and   the 
Rec'tum.     (Appendix  D.) 

245.  The  DUODENUM  is  somewhat  larger  than  the  rest  of 
the  small  intestine,  and  has  received  its  name  from  being  in 

244.  Explain  fig.  60.  What  is  the  length  of  the  small  intestine,  and 
how  is  it  divided  ?  What  is  the  length  of  the  large  intestine  ?  Give  its 
divisions.  245.  Describe  the  duodenum. 


118  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

length  about  the  breadth  of  twelve  fingers.  It  commences  at 
the  pylorus,  and  ascends  obliquely  backward  to  the  under 
surface  of  the  liver.  It  then  descends  perpendicularly  in 
front  of  the  right  kidney,  and  passes  transversely  across  the 
lower  portion  of  the  spinal  column,  behind  the  colon,  and 
terminates  in  the  jejunum.  The  ducts  from  the  liver  and 
pancreas  open  into  the  perpendicular  portion,  about  six  inches 
from  the  stomach. 

246.  The  JEJUNUM  is  continuous  with  the  duodenum.     It 
is  thicker  than   the  rest  of  the   small   intestine,  and  has  a 
pinkish  tinge. 

247.  The   ILEUM  is  smaller,  and   thinner  in  texture,  and 
somewhat  paler,  than  the  jejunum.     There  is  no  mark  to  dis- 
tinguish the  termination  of  the  one  or  the  commencement  of 
the  other.     The  ileum  terminates  near  the  right  haunch-bone, 
by  a  valvular  opening  into  the  colon   at  an  obtuse   angle. 
This  arrangement  prevents  the  passing  of  substances  from  the 
colon  into   the  ileum.      The    jejunum    and  ileum    are   sur- 
rounded above  and  at  the  sides  by  the  colon. 

248.  The  small  intestine,  like  the  stomach,  has  three  coats. 
The  inner,  or  mucous  coat  is  thrown  into  folds,  or  valves.     In 
consequence  of  this  valvular  arrangement,  the  mucous  mem- 
brane is  more   extensive  than  the  other  tissues,  and  gives  a 
greater  extent  of  surface  with  which  the  aliment  comes  in 
contact.      There   are    imbedded    under    this    membrane    an 
immense  number  of  minute  glands,  and  it  has  a  great  number 
of  piles,  like  those  upon  velvet.     For  this  reason,  this  mem- 
brane is  sometimes  called  the  vil'lous  coat. 

249.  The  CCECUM  is  the  blind  pouch,  or  cul-de-sac,  at  the 
commencement  of  the  large  intestine.     Attached  to  its  ex- 
tremity  is   the    ap-pend'ix    verm-i-form'is,    (a   long,   worm- 

What  important  ducts  open  into  it  ?  246.  Describe  the  jejunum. 
247.  The  ileum.  248.  What  is  said  of  the  coats  of  the  intestines  ?  Why 
is  the  mucous  membrane  sometimes  called  the  villous  coat  ?  249.  Describe 
the  coecum. 


ANATOMY    OF    THE    DIGESTIVE    ORGANS. 


119 


shaped  tube.)     It  is  from  one  to  six  inches  in  length,  and  of 
..he  size  of  a  goose-quill. 

250.  The  COLON  is  divided  into  three  parts  —  the  ascending^ 
transverse,  and  descending.  The  ascending  colon  passes 
upward  from  the  right  haunch-bone  to  the  under  surface  of 
the  liver.  It  then  bends  inward,  and  crosses  the  upper  part 
of  the  abdomen,  below  the  liver  and  stomach,  to  the  left  side 
under  the  name  of  the  transverse  colon.  At  the  left  side,  it 
turns,  and  descends  to  the  left  haunch-bone,  and  is  called  the 
descending  colon.  Here  it  makes  a  peculiar  curve  upon  itself, 
which  is  called  the  sig'moidfletfure. 

Fig.  61. 


Fig.  61.  1,  1,  The  duodenum.  2,  2,  The  small  intestine.  3,  The  junction  of  the 
small  intestine  with  the  colon.  4,  The  appendix  vermiforrnis.  5,  The  ccecum.  6,  The 
ascending  colon.  7,  The  transverse  colon.  8,  The  descending  colon.  9,  The  sig- 
moid  flexure  of  the  colon.  10,  The  rectum. 


2,50.  Describe  the  course  of  the  divisions  of  the  colon.     Explain,  fg.  61. 


120  ANATOMY,    PHYSIOLOGY,   ANP    HYGIENE. 

251.  The  RECTUM  is  the  termination  of  the  large  intestine. 
The  large   intestine   has   three  coats,  like  the  stomach  and 
small  intestine.     The  longitudinal  fibres  of  the  muscular  coat 
are  collected  into  three  bands.     These  bands  are  nearly  one 
half  shorter    than   the   intestine,  and    give   it    a  sacculated 
appearance,  which  is  characteristic  of  the  coecum  and  colon. 

252.  The  LACTEALS  are  minute  vessels,  which  commence 
in  the  villi,  upon  the  mucous  surface  of  the  small  intestine. 
From  the  intestine  they  pass  between  the  membranes  of  the 
mes'en-ter-y   to   small   glands,  which  they  enter.     The  first 
range  of  glands  collects  many  small  vessels,  and  transmits  a 
few  larger  branches  to  a  second  range  of  glands ;  and,  final- 
ly, after  passing  through  several  successive   ranges  of  these 
glandular  bodies,  the   lacteals,  diminished  in  number  and  in- 
creased in  size,  proceed  to  the  enlarged  portion  of  the  thoracic 
duct,  into  which  they  open.     They  are  most  numerous  in  the 
upper  portion  of  '.he  small  intestine. 

253.  The  THORACIC  DUCT  commences  in  the  abdomen,  by 
a  considerable  dilatation,  which  is  situated  in  front  of  the  lower 
portion   of  the   spinal  column.     From   this  point,  it   passes 
through  the  diaphragm,  and  ascends  to  the  lower  part  of  the 
neck.     In  its  ascent,  it  lies  anterior  to  the  spine,  and  by  the 
side  of  the  aorta  and  O3sophagus.     At  the  lower  part  of  the 
neck,  it  makos  a  sudden  turn  downward  and  forward,  and 
terminates  by  opening  into  a  large  vein  which  passes  to  the 
heart.     The  thoracic  duct  is  equal  in  diameter  to  a  goose- 
quill,  and,  at  its  termination,  is  provided  with  a  pair  of  semi- 
lunar  valves,  which  prevent  the  admission  of  venous  blocd 
into  its  cylinder. 

251.  What  is  said  of  the  arrangement  of  the  fibres  of  the  muscular  coat 
of  the  laige  intestine?  252.  What  are  the  lacteals  ?  Give  their  course 
from  the  mucous  coat  of  the  intestine  to  the  thoracic  duct.  253.  Describe 
the  course  of  the  thoracic  duct.  How  is  the  venous  blood  prevented  from 
passing  into  this  duct  ? 


tf ATOMY    OF    THE    DIGESTIVE    ORGANS. 
Fig.   62. 


12  i 


fig  6J>  A  portion  of  the  small  intestine,  lacteal  vessels,  mesenteric  glands,  and 
thoracic  duct.  1,  The  intestine.  2,  3,  4,  Mesenteric  glands,  through  which  the 
.acteate  pass  to  the  thoracic  duct.  5, 6,  The  thoracic  duct.  7,  The  point  in  the  neck 
where  it  turns  down  to  enter  the  vein  at  8.  9,  10,  The  aorta.  11,  12,  Vessels  of  the 
neck.  13,  14,  15,  The  large  veins  that  convey  the  blood  and  chyle  to  the  heart. 
"",  17,  The  spinal  column.  18,  The  diaphragm,  (midriff.) 

Observation.  The  mesenteric  glands,  which  are  situated 
between  two  layers  of  serous  membrane  (mesentery)  that 
connects  the  small  intestine  with  the  spinal  column,  occasion- 
ally become  diseased  in  childhood,  arid  prevent  the  chyle 

Explain  fig.  62.    What  is  said  respecting  the  mesenteric  glands  ? 
1! 


122  ANATOMY,    PHYSIOLOGY,    AND    HYGIEI^fc. 

from  passing  to  the  thoracic  duct.  Children  thus  affected  have 
a  voracious  appetite,  and  at  the  same  time  are  becoming  more 
and  more  emaciated.  The  disease  is  called  mesenteric  con- 
sumption. 

254.  The  LIVER,  a  gland  appended  to  the  alimentary  canal, 
is  the  largest  organ  in  the  system,  and  weighs  about  foui 
pounds.  It  is  situated  in  the  right  side,  below  the  diaphragm, 
and  is  composed  of  several  lobes.  Its  upper  surface  is  con- 
vex ;  its  under,  concave.  This  organ  is  retained  in  its  place 
by  several  ligaments.  It  performs  the  double  office  of  sepa- 
rating impurities  from  the  venous  blood,  and  of  secreting  a 
fluid  (bile)  necessary  to  chylification.  On  the  under  surface 
of  the  liver  is  a  membranous  sac,  called  the  gall-cyst,  which 
3s  generally  considered  as  a  reservoir  for  the  bile. 

Fig.  63. 


Fig.  63.  The  under  surface  of  the  Hver.  1,  The  right  lobe.  2,  The  left.  3, 4, 
Smaller  lobes.  10,  The  gall-bladder,  or  cyst,  lodged  in  its  depression.  17,  The  notch 
on  the  posterior  border,  for  the  spinal  column. 

< 

Observation.  A  good  idea  of  the  liver  and  intestines  can 
be  obtained  by  examining  these  parts  of  a  pig.  In  this  animal, 
the  sacs,  or  pouches,  of  the  large  intestine  are  well  denned. 

255.  The  PANCREAS  is  a  long,  flattened  gland,  analogous  to 

254.  Describe  the  liver.     255.  What  is  said  of  the  pancreas  ? 


ANATOMY    OF    THE    DIGESTIVE    ORGANS.  123 

the  salivary  glands.  It  is  about  six  inches  in  length,  weighs 
three  or  four  ounces,  and  is  situated  transversely  across  the 
posterior  wall  of  the  abdomen,  behind  the  stomach.  A  duct 
from  this  organ  opens  into  the  duodenum. 

256.  The  SPLEEN,  (milt,)  so  called  because  the  ancients 
supposed  it  to  be  the  seat  of  melancholy,  is  an  oblong,  flat- 
tened organ,  situated  in  the  left  side,  in  contact  with  the  dia- 
phragm, stomach,  and  the  pancreas.  It  is  of  a  dark,  bluish 
color,  and  is  abundantly  supplied  with  blood,  but  has  no  duct 
which  serves  as  an  outlet  for  any  secretion.  Its  use  is  not 
well  determined. 

Fig.  64. 


.  64.    The  pancreas  with  its  duct,  through  which  the  pancreatic  secretion  passei 
!mo  the  duodenum. 

257.  The   OMENTUM  (caul)  consists  of  four  layers  of  the 
serous    membrane,  which   descends  from    the  stomach  and 
transverse  colon.     A  quantity  of  adipose  matter  is  deposited 
around  its  vessels,  which   ramify  through  its  structure.     Its 
function  is  twofold   in  the  animal  economy.     1st.  It  protects 
the   intestines  from  cold.     2d.  It  facilitates  the   movements 
of  the  intestines  upon  each  other  during  their  vermicular,  or 
worm-like  action. 

258.  Every  part  of  the  digestive  apparatus  is  supplied  with 
arteries,  veins,  lymphatics,  and  nervous  filaments,  from  the 
gangiionic  system  of  nerves. 

2-56.  Why  is  the  spleen  so  called  ?  What  is  peculiar  to  this  organ  ? 
257.  Of  what  is  the  omentum  composed  ?  What  is  its  use  ?  258.  With 
what  is  every  part  of  the  digestive  apparatus  supplied  ? 


124  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

CHAPTER    XIV. 

PHYSIOLOGY    OF    THE    DIGESTIVE    OKGANS. 

& 

259.  SUBSTANCES  received  into  the  stomach  as  food,  must 

necessarily  undergo  many  changes  before  they  are  fitted  to 
form  part  of  the  animal  body.  The  solid  portions  are  re- 
duced to  a  fluid  state,  and  those  parts  that  will  nourish  the 
body  are  separated  from 'the  waste  material. 

260.  The  first  preparation  of  food   for  admission  into  the 
system,  consists  in  its  proper  mastication.     The  lips  in  front, 
the  cheeks  upon  the  side,  the  soft  palate,  by  closing  down 
upon  the  base  of  the  tongue,  retain  the  food  in  the  mouth, 
while  it  is  subjected  to  the   process  of  mas-ti-ca'tion,  (chew- 
ing.)   The  tongue  rolls  the  mass  around,  and  keeps  it  between 
the  teeth,  while  they  divide  the  food  to  a  fineness  suitable  for 
the  stomach. 

261.  While  the  food   is  in  process  of  mastication,  there  is 
incorporated  with  it  a  considerable  amount  of  sa-U'va,  (spittle.) 
This  fluid  is  furnished  by  the  salivary  glands,  situated  in  the 
vicinity  of  the    mouth.     The  saliva  moistens  and  softens   the 
food,  so  that,  when  carried  into  the  pharynx,  it  is  passed,  with 
ease,  through  the  oesophagus  into  the  stomach. 

262.  When  the  food  has  been  properly  masticated,  (and  in 
rapid  eaters  when  it  is  not,)  the  soft  palate  is  raised  from  the 
base  of  the  tongue  backward,  so  as  to  close  the  posterior  open- 
ing through  the  nostrils.     By  a  movement  of  the  muscles  of 
the  tongue,  cheeks,  and  floor  of  the  mouth,  simultaneous  with 

259 — 272.  Give  the  physiology  of  the  digestive  organs.  259.  "Whatisneces 
sary  before  food  can  nourish  the  body  ?  260.  Describe  how  mastication  ia 
performed.  261.  Of  what  use  is  the  saliva  in  the  process  of  mastication  ? 
262.  How  is  the  food  pressed  into  the  pharynx  ? 


PHYSIOLOGY    OF    THE    DIGESTIVE    ORGANS.  125 

that  of  the  soft  palate,  the  food  is  pressei  into  the  upper  part 
of  the  pharynx. 

263.  When  in  the  pharynx,  the  food   and  drink  are  pre- 
vented from  passing  into  the  trachea  by  a  simple  valve-like 
arrnngement,  called  the  ep-i-glot'tis.     The   ordinary  position 
of  this  little  organ  is  perpendicular,  so  as  not  to  obstruct  the 
passage  of  air  into  the  lungs ;  but  in  the  act  of  swallowing, 
it  is  brought  directly  over  the  opening  of  the  trachea,  called 
the  glottis.     The  food,  being  forced  backward,  passes  rapidly 
over  the  epiglottis  into  the  oesophagus,  where  the  circular  band 
of  muscular  fibres  above,  contracts  and  forces  the  food  to  the 
next  lower  band.     Each  band  relaxes  and  contracts  succes- 
sively, and   thus   presses  the  alimentary  ball  downward  and 
onward  to  the  stomach.* 

Observation.  If  air  is  inhaled  when  the  food  or  drink  is 
passing  over  the  glottis,  some  portions  of  it  may  be  carried 
into  the  larynx  or  trachea.  This  produces  violent  spasmodic 
coughing,  and  most  generally  occurs  when  an  attempt  is  made 
to  speak  while  masticating  food ;  therefore,  never  talk  when 
the  mouth  contains  food. 

264.  When  the  food  reaches  the  stomach,  the  gastric  glands 
are  excited  to  action,  and  they  secrete  a  powerful  solvent, 
called  gastric  juice.    The  presence  of  food  in  the  stomach  also 
increases  a  contractile  action  of  the  muscular  coat,  by  which 
the  position  of  the  food  is  changed  from  one  part  of  this  cavity 
to  another.     Thus  the  aliment  is  brought  in  contact  with  the 
mucous  membrane,  and  each  portion  of  it  becomes  saturated 
with  gastric  juice,  by  which  it  is  softened,  or  dissolved  into 


*  The  process  of  deglutition  may  be  comprehended  by  analyzing 
the  operation  of  swallowing  food  or  saliva. 

263.  When  the  food  is  in  the  pharynx,  how  is  it  prevented  from  passing 
into  the  trachea,  or  windpipe  ?  Describe  how  it  is  passed  into  the  stom- 
ach ?  Give  the  observation.  264.  Describe  how  the  food  in  the  stomach 
is  converted  into  clyme. 

11  * 


126  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

a  pulpy  homogeneous  ma«*f  of  a  creamy  consistence,  called 
Chyme.  The  food  is  not  all  converted  into  chyme  at  the  same 
time  ;  but  as  fast  as  it  is  changed,  it  passes  through  the  pyloric 
orifice  into  the  duodenum. 

Observation.  The  gastric  juice  has  the  property  of  coagu- 
lating liquid  albuminous  matter  when  mixed  with  it.  It  is 
this  property  of  rennet,  which  is  an  infusion  of  the  fourth 
stomach  of  the  calf,  by  which  milk  is  coagulated,  or  formed 
into  "  curd." 

265.  The  CHYME  is  conveyed  through  the  pyloric  orifice  of 
the  stomach  into  the  duodenum.     The  chyme  not  only  excites 
an  action  in  the  duodenum,  but  also  in  the  liver  and  pancreas. 
Mucus  is  then  secreted  by  the  duodenum,  bile  by  the  liver, 
and  pancreatic  fluid  by  the  pancreas.     The  bile  and  pancre- 
atic fluid  are  conveyed  into  the  duodenum,  and  mixed  with 
the  chyme.     By  the  action  of  these  different  fluids,  the  chyme 
is  converted  into  a  fluid  of  a  whitish  color,  called  Chyle,  and 
into  residuum. 

Observation.  The  bile  has  no  agency  in  the  change 
through  which  the  food  passes  in  the  stomach.  In  a  healthy 
condition  of  this  organ,  no  bile  is  found  in  it.  The  common 
belief,  that  the  stomach  has  a  redundancy  of  this  secretion,  is 
erroneous.  If  bile  is  ejected  in  vomiting,  it  merely  shows, 
not  only  that  the  action  of  the  stomach  is  inverted,  but  also 
that  of  the  duodenum.  A  powerful  emetic  will,  in  this  way, 
generally  bring  this  fluid  from  the  most  healthy  stomach.  A 
knowledge  of  this  fact  might  save  many  a  stomach  from  the 
evils  of  emetics,  administered  on  false  impressions  of  tneir 
necessity,  and  continued  from  the  corroboration  of  these  by 
the  appearance  of  bile,  till  derangement,  and  perhaps  perma 
nent  disease,  are  the  consequences. 

266.  The  CHYLE  and  residual  matter  are  moved    over  the 

What  peculiar  property  has  gastric  juice  ?  265.  "Where  and  how  is 
chyme  converted  into  chyle  ?  What  is  said  in  regard  to  the  bile  ?  266.  What 
b«  comes  of  the  chyle  ? 


PHYStOLJGY    OF    THE    DIGESTIVE    ORGANS.  127 

mucous  surface  of  the  small  intestine,  by  the  action  of  its 
muscular  coat.  As  the  chyle  is  carried  along  the  tract  of  the 
intestine,  it  comes  in  contact  with  the  villi,  where  the  lacteal 
vessels  commence.  These  imbibe,  or  take  up,  the  chyle,  and 
transfer  it  through  the  mesenteric  glands  into  the  thoracic  duct, 
through  which  it  is  conveyed  into  a  large  vein  at  the  lower 
part  of  the  neck.  In  this  vein  the  chyle  is  mixed  with  the 
venous  fluid.  The  residual  matter  is  conveyed  into  the  large 
intestine,  through  which  it  is  carried  and  excreted  from  the 
system.  (Appendix  E.) 

267.  In  the  process  of  digestion,  the  food  is  subjected  to 
five  different  changes.      1st.  The  chewing  and  admixture  of 
the  saliva  with  the  food  ;  this  process  is  called  mastication. 

268.  2d.  The   change  through  which  the   food  passes  in 
the  stomach  by  its  muscular  contraction,  and  the  secretion 
from  the  gastric  glands ;  this  is  called  chymification. 

269.  3d.  The  conversion  of  the  homogeneous  chyme,  by 
the  agency  of  the  bile  and  pancreatic  secretions,  into  a  fluid 
of  milk-like  appearance  ;  this  is  cliylification. 

270.  4th.  The  absorption  of  the    chyle  by    the  lacteals, 
and  its  transfer  through  them  and  the  thoracic  duct,  into  the 
subclavian  vein  at  the  lower  part  of  the  neck.* 

271.  5th.  The  separation  and  excretion  of  the  residuum. 

272.  Perfection  of  the  second  process  of  digestion  requires 
thorough  and   slow    mastication.     The    formation   of  proper 
chyle  demands   appropriate    mastication  and  chymification  ; 
while  a  healthy  action  of  the  lacteals   requires  that  all   the 
anterior  stages   of  the   digestive   process   be   as  perfect  a? 
possible.     (Appendix  F.) 


*  The  chyle  is  changed  by  the  lacteals  and  mesenteric  glands,  but 
the  nature  of  this  change  is  not,  as  yet,  well  defined  or  understood. 

Of  the  residuum  ?    267.  Recapitulate  the  five  changes  in  the  digestive 
process. 

Note.    Let  the  pupil   review  the  anatomy  and  physiology  of  the  digestive  organ*, 
from  figs.  62  and  G5,  or  from  anatomiciil  outline  plate  No.  5. 


t-J* 


ANATOMY,    PlfVSJOLOGV,    ANI>   l!Yt;iEN£. 
Kg.  65. 


1-13 


FIJI  65i  An  idea)  view  of  the  organs  of  digestion,  opened  nearly  the  w?»ote  length 
I,  The  upper  jaw.  2,  The  lower  jaw.  3,  The  tongue.  4,  The  roof  of  the  mouth 
5,  The  oesophagus.  6,  The  trachea.  7,  The  parotid  gland.  8,  The  sublingual  gland 
9,  The  stomach.  10,  10,  The  liver.  11,  The  gall-cyst.  12,  The  duct  that  conveys 
the  bile  to  the  duodenum,  (13,  13.)  14,  The  pancreas.  15, 15,  15,  15,  The  small  in 
U-snne.  )(5,  The  opening  of  the  small  intestine  into  the  lerge  intestine.  17, 18, 19,20 
''he  large  intestine  21,  The  spleen.  22,  The  upper  part  of  the  spinal  column 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  129 

CHAPTER     XV. 

HYGIENE    OF    THE    DIGESTIVE    ORGANS. 

273.  IT  is  a  law  of  the  system,  that  each  organ  is  excited 
to  healthy  and  efficient  action,  when  influenced  by  its  appro- 
priate stimulus.     Accordingly,  nutrient  food,  that  is  adapted 
to  the  wants  of  the  system,  imparts  a  healthy  stimulation  tc 
the  salivary  glands  during  the   process  of  mastication.     The 
food  that  is  well  masticated,  and  has  blended  with  it  a  prope 
amount  of  saliva,  will  induce  a  healthy  action  in  the  stomach 
Well-prepared  chyme  is  the  natural  stimulus  of  the  duodenum 
liver,  and  pancreas ;  pure  chyle  is  the  appropriate  excitant  of 
the  lacteal  vessels. 

274.  The  perfection  of  the  digestive  process,  as  well  aa 
the  health  of  the  general   system,  requires  the  observance  of 
certain   conditions.     These    will   be    considered   under   four 
heads :  —  1st.  The  Quantity   of  food  that  should   be    taken. 
2d.    Its  Quality.     3d.  The  Manner   in    which  it   should    be 
taken.     4th.   The    Condition  of  the    system    when    food    is 
taken. 

275.  The    QUANTITY   of  food    necessary  for   the    system 
varies.     Age,  occupation,  temperament,  temperature,  habits 
amount  of  clothing,  health  and  disease  are  among  the  circum- 
stances which  produce  the  variation. 

276.  The   child   and  youth  require  food  to  promote   the 

273 — 330.  Give  the  hygiene  of  the  digestive  organs.  273.  Give  a  law 
of  the  system.  What  is  the  appropriate  stimulus  of  the  salivary  glands 
during  mastication?  Of  the  stomach?  Of  the  duodenum?  Of  the 
lacteal  vessels?  274.  What  does  the  perfection  of  the  digestive  organs 
require  ?  275.  What  exert  an  influence  on  the  quantity  of  food  necessary 
tor  the  system  ? 


.30  ANATOMY,    PHYSIOLOGY,   AND    HYGlEiNE. 

growth  of  the  different,  parts  of  the  body.  The  more  rapid 
the  growth  of  the  child,  the  greater  the  demand  for  food. 
This  accounts  for  the  keen  appetite  and  vigorous  digestion  in 
childhood.  When  the  youth  has  attained  his  full  growth,  this 
necessity  for  nutriment  ceases ;  after  this  period  of  life,  if  the 
same  amount  of  food  is  taken,  and  there  is  no  increase  of 
labor  or  exertion,  the  digestive  apparatus  will  become  diseased, 
and  the  vigor  of  the  whole  system  diminished. 

Observation.  When  the  body  has  become  emaciated  from 
want  of  nutriment,  either  from  famine  or  disease,  there  is  an 
increased  demand  for  food.  This  may  be  gratified  with 
impunity  until  the  individual  has  regained  the  usual  size,  but 
repletion  should  be  avoided. 

277.  Food  is  required  to  repair  the  waste,  or  loss  of  sub- 
stance that  attends  action.     In  every  department  of  nature, 
waste,  or  loss  of  substance,  attends  and  follows  action.    When 
an  individual  increases  his  exercise,  — changes  from  light  to  se- 
vere labor,  —  or  the  inactive  and  sedentary  undertake  journeys 
for  pleasure,  the  fluids  of  the  system  circulate  with  increased 
energy.     The  old  and  exhausted  particles  of  matter  are  more 
rapidly  removed  through  the  action  of  the  vessels  of  the  skin, 
lungs,'  kidneys,  and  other  organs,  and  their  places  are  filled 
with  new  atoms,  deposited  by  the  small  blood-vessels. 

278.  As  the  chyle  supplies  the  blood  with  the  newly  vital- 
ized particles  of  matter,  there  is,  consequently,  an  increased 
demand    for    food.      This   want   of  the   system    induces,  in 
general,  a  sensation  of  hunger  or  appetite,  which    may  be 
regarded  as  an  indication  of  the  general  state  of  the  body. 
The  sympathy  that  exists  throughout  the  system  accords  to 

276.  At  what  age  is  the  appetite  keen  and  the  digestion  vigorous  ?  Why  ? 
What  is  said  in  regard  to  the  quantity  of  food  when  the  youth  has  attained 
his  growth  ?  What  exception,  as  given  in  the  observation  ?  277.  Give 
another  demand  for  food.  What  effect  has  increased  exercise  upon  the 
system  ?  278  How  are  the  new  particles  of  matter  supplied  ?  What  doen 
this  induce  ? 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  Ji 

the  stomach  the  power  of  making  known  this  state  to  the 
nervous  system,  and,  if  the  functions  of  this  faithful  monitor 
have  not  been  impaired  by  disease,  abuse,  or  habit,  the  call  is 
imperious,  and  should  be  regarded. 

279.  WJien  exercise  or  labor  is  lessened,  tlie  quantity  of 
food  should  be  diminished.     When  a  person  who  has  been 
accustomed  to  active  exercise,  or  even  hard  manual  labor, 
suddenly  changes  to  an  employment  that  demands  less  activity, 
the  waste  attendant  on  action  will  be  diminished   in  a  cot- 
responding   degree ;   hence  the  quantity  of  food    should  be 
lessened    in  nearly  the    same    proportion    as  the  amount  of 
exercise  is  diminished.     If  this  principle  be  disregarded,  the 
tone  of  the  digestive   organs  will  be  impaired,  and  the  health 
of  the  system  enfeebled. 

280.  This  remark  is  applicable  to  those  students  who  have 
left  laborious  employments  to  attend  school.     Although  the 
health  is  firm,  and  the  appetite  keen  from   habit,  yet  every 
pupil  should  practise  some  self-denial,  and  not  eat  as  much  as 
the  appetite  craves,  the  first  week  of  the  session.     After  some 
days,  the  real  wants  of  the  system  will  generally  be  manifested 
by  a  corresponding  sensation  of  hunger. 

Observation.  It  is  a  common  observation  that  in  academies 
and  colleges,  the  older  students  from  the  country,  who  have 
been  accustomed  to  hard  manual  labor,  suffer  more  frequently 
from  defective  digestion  and  impaired  health  than  the  younger 
and  feebler  students  from  the  larger  towns  and  cities. 

281.  Food  is  essential  in  maintaining  a  proper  temper- 
ature of  t lie  system.     The  heat  of  the  system,  at  least  in  part, 
is  produced  in  the  minute  vessels  of  the  several  organs,  by  the 
union  of  oxygen  with  carbon  and  hydrogen,  which  the  food 
and  drink  contain.     The  amount  of  heat  generated,  is  greut- 

279.  Why  should  the  quantity  of  food  be  diminished  when  the  exercise 
is  lessened  ?  What  effect  if  this  principle  be  disregarded  ?  280.  To  what 
class  is  this  remark  applicable  ?  What  is  often  observed  among  students 
in  academies  and  colleges  ?  281.  State  another  demand  for  food.  What  is 
one  source  of  heat  in  the  body  ? 


13%  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

est  when  it  is  most  rapidly  removed  from  the  system,  which 
occurs  in  cold  weather.  This  is  the  cause  of  the  system 
requiring  more  food  in  winter  than  summer. 

Observation.     Persons  that  do  not  have  food  sufficient  for 
the  natural  wants  of  the  system,  require  more  clothing  than 
who  are  well  fed. 

The  last-mentioned  principle  plainly  indicates  the 
propriety  and  necessity  of  lessening  the  quantity  of  food  as 
the  warm  season  approaches.  Were  this  practised,  the  tone 
of  the  stomach  and  the  vigor  of  the  system  would  continue 
unimpaired,  the  "  season  complaints  "  would  be  avoided,  and 
the  "  strengthening  bitters "  would  not  be  sought  to  create 
an  appetite. 

Observation.  Stable-keepers  and  herdsmen  are  aware  of 
the  fact,  that  as  the  warm  season  commences,  then  animals 
require  less  food.  Instinct  teaches  these  animals  more  truly, 
in  this  particular,  than  man  allows  reason  to  guide  him. 

283.  The  quantity  of  food  should  have  reference  to  the 
present  condition  of  the  digestive  organs.     If  they  are  weak- 
ened or  diseased,  so  that  but  a  small  quantity  of  food  can  be 
properly   digested  or  changed,  that  amount  only  should  be 
taken.     Food  does  not  invigorate   the    system,  except   it  is 
changed,  as  has  been  described  in  previous  paragraphs. 

Observation.  When  taking  care  of  a  sick  child,  the  anxiety 
of  the  mother  and  the  sufferings  of  the  child  may  induce  her 
to  give  food  when  it  would  be  highly  injurious.  The  attend- 
ing physician  is  the  only  proper  person  to  direct  what  quantity 
should  be  given. 

284.  The  quantity  of  food  is  modified,  in  some  degree,  by 

Why  do  we  eat  more  in  the  winter  than  in  the  summer  ?  What  practi- 
cal observation  is  given?  282.  Why  should  the  quantity  of  food  be 
lessened  as  warm  weather  commences  ?  What  would  be  avoided  if  this 
principle  were  obeyed  ?  283.  Why  should  the  present  condition  of  the 
di Costive  organs  be  regarded  in  reference  to  the  quantity  of  food  ?  .Mention 
*;i  Mistiinirc  in  which  it  would  be  injudicious  to  give  food. 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  133 

habit.  A  healthy  person,  whose  exercise  is  in  pure  aL,  may 
be  accustomed  to  take  more  food  than  is  necessary.  The 
useless  excess  is  removed  from  the  system  by  the  waste  out- 
lets, as  the  skin,  lungs,  liver,  kidneys,  &c.  In  such  cases, 
if  food  is  not  taken  in  the  usual  quantity,  there  will  be  a  feel 
ing  of  emptiness,  if  not  of  hunger,  from  the  want  of  the  usual 
distention  of  the  stomach.  This  condition  of  the  digestive 
jrgans  may  be  the  result  of  disease,  but  it  is  more  frequently 
produced  by  inordinate  daily  indulgence  in  eating,  amounting 
almost  to  gluttony. 

285.  Large  quantities  of  food  oppress  the  stomach,  and 
cause  general  languor  of  the  whole  body.     This  is  produced 
by  the  extra  demands  made  on  the  system  for  an  increased 
supply  of  blood  and  nervous  fluid  to  enable  the  stomach  to 
free  itself  of  its  burden.     Thus,  when  we  intend  to  make  any 
extraordinary  effort,  mental  or  physical,  at  least  for  one  meal, 
we  should  eat  less  food  than  usual,  rather  than  a  greater 
quantity. 

286.  No   more  food  should  be  eaten  than  is  barely  suf- 
ficient to  satisfy  the  appetite.     Nor  should  appetite  be  con- 
founded with  taste.     The  one  is  a  natural   desire  for  food  to 
supply  the  wants  of  the  system  ;  the  other  is  an   artificial 
desire  merely  to  gratify  the  palate. 

287.  Although  many  things  may  aid  us  in  determining  tne 
quantity  of  food   proper  for  an  individual,  yet  there  is  no 
certain  guide  in  all  cases.     It  is  maintained  by  some,  that  the 
sensation  of  hunger  or  appetite  is  always  an  indication  of  the 
want  of  food,  while  the  absence  of  this  peculiar  sensation  is 
regarded  as  conclusive  evidence  that  aliment  is  not  demanded. 


284.  Show  the  effect  of  habit  upon  the  quantity  of  food  that  is  eaten. 
What  is  said  in  regard  to  inordinate  eating  ?  285.  What  is  the  effect  of 
eating  large  quantities  of  food  ?  What  suggestion  when  an  extraordinary 
effort,  either  mental  or  physical,  is  to  be  made  ?  286.  How  much  food 
should  generally  be  eaten  ?  287.  What  is  the  assertion  of  some  persons 
re:ative  to  the  quantity  of  food  necessary  for  the  system  ? 

r> 


134  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

This  assertion  is  not  correct,  as  an  appetite  may  be  created 
for  food  by  condiments  and  gormandizing,  which  is  as  arti- 
ficial and  as  morbid  as  that  which  craves  tobacco  or  ardent 
spirits.  On  the  other  hand,  a  structural  or  functional  disease 
of  the  brain  may  prevent  that  organ  from  taking  cognizance 
of  the  sensations  of  the  stomach,  when  the  system  actually 
requires  nourishment.  Observation  shows,  that  disease,  habit, 
the  state  of  the  mind,  and  other  circumstances,  exert  an 
influence  on  the  appetite. 

Observation.  Dr.  Beaumont  noticed,  in  the  experiments 
upon  Alexis  St.  Martin,  that  after  a  certain  amount  of  food 
was  converted  into  chyme,  the  gastric  juice  ceased  to  ooze 
from  the  coats  of  the  stomach.  Consequently,  it  has  been 
inferred  by  some  writers  on  physiology,  that  the  glands  which 
supply  the  gastric  fluid,  by  a  species  of  instinctive  intelligence, 
would  only  secrete  enough  fluid  to  convert  into  chyme  the 
aliment  needed  to  supply  the  real  wants  of  the  system.  What 
are  the  reasons  for  this  inference  ?  There  is  no  evidence  thai 
the  gastric  glands  possess  instinctive  intelligence,  and  can 
there  be  a  reason  adduced,  why  they  may  not  be  stimulated 
to  extra  functional  action  as  well  as  other  organs,  and  why 
they  may  not  also  be  influenced  by  habit  ? 

288.  While   all   agree    that   the    remote    or   predisposing 
cause  of  hunger  is,  usually,  a  demand  of  the  system   for 
nutrient  material,  the  proximate  or  immediate  cause  of  the 
sensation  of  hunger  is  not  clearly  understood.     Some  phys- 
iologists suppose  that  it  is  produced  by  an  engorged  condition 
of  the  glands  of  the  stomach  which  supply  the  gastric  juice  ; 
while  others    maintain  that  it  depends  on  a  peculiar  condi- 
tion of  the  nervous  system. 

289.  The  QUALITY  of  the  food  best  adapted  to  the  wants  of 
the  system  is  modified  by  many  circumstances.     There  are 

What  does  observation  show  ?  288.  What  is  said  of  the  causes  of 
hunger?  289.  Why  is  not  the  same  kind  of  food  adapted  to  different 
individuals  ? 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  135 

many  varieties  of  food,  and  these  are  much  modified  by  the 
different  methods  of  preparation.  The  same  kind  of  food  is 
not  equally  well  adapted  to  different  individuals,  or  to  the 
same  individual  in  all  conditions  ;  as  vocation,  health,  exposure, 
labits  of  life,  season,  climate,  &c.,  influence  the  condition  of 
.he  system. 

290.  All  articles  of  food  may  be  considered  in  two  rela- 
tions :   1st,  As  nutritive.     2d,  As  digestible.     Substances  are 
nutritious  in  proportion  to  their  capacity  to  yield  the  elements 
of  chyle,  of  which  carbon,  oxygen,  hydrogen,  and   nitrogen 
are   the  most  essential;  they  are  digestible  in  proportion  to 
the  facility  with  which  they  are  acted  upon   by  the  gastric 
juice.     These   properties   should  not   be  confounded  in  the 
various  articles  used  for  food. 

291.  As  a  "  living  body  has  no  power  of  forming  elements, 
or  of  converting  one   elementary  substance  into  another,  it 
therefore  follows  that  the  elements  of  which  the  body  of  an 
animal  is  composed  must  be  in  the  food."     (Chap.  III.)     Of 
:he  essential  constituents  of  the  human  body,  carbon,  hydro- 
gen, oxygen,  and  nitrogen  are  the  most  important,  because 
they  compose  the  principal  part  of  the  animal  body ;  while 
the  other  elements  are  found  in  very  small  proportions,  and 
many  of  them  only  in  a  few  organs  of  the  system.     (Appen- 
dix G.) 

Observation.  Nitrogen  renders  food  more  stimulating,  par- 
ticularly if  combined  with  a  large  quantity  of  carbon,  as  beef. 
Those  articles  that  contain  the  greatest  amount  of  the  con- 
stituent elements  of  the  system  are  most  nutritious.  As  milk 
and  eggs  contain  all  the  essential  elements  of  the  human  sys- 
tem, so  they  are  adapted  to  almost  universal  use,  and  are 
highly  nutritious. 

292.  The  following  table,  by  Pereira,  in  his  treatise  on 


290.  In  what  proportion  are  substances   nutritious  ?      Digestible  1      YViif 
does  benf  stimulate  the  system  ?     What  is  said  of  milk  and  eggs  ? 


ANATOMY,    PHYSIOLOGY,    /  ND    HYGIENE. 


Food  and  Diet,  $?&$<•  aid  the  student  in  approximating  tc 
correct  conclusions  of  the  quantity  of  nutriment  in  different 
kinds  of  food,  and  its  adaptation  to  the  wants  of  tne  system. 


TABLE, 

SHOWING   THE   AVERAGE   QUANTITY   OF  DRY,    OR  SOLID   MATTER,    CARBON, 
NITROGEN,  AND   MOISTURE,  IN   DIFFERENT  ARTICLES   OF  DIET. 


One  hundred  Parts. 

Dry 

Matter. 

Carbon. 

Nitrogen. 

Water 

81.8 

36.4 

18.2 

Beans,  

85.89 

38.24 

14.11 

Beef,  fresh,  

25 

12.957 

3.752 

75 

Bread,  rye,  

67.79 

30.674 

32.21 

Butter,.  .                   ... 

100 

656 

Cabbage,  . 

7.7 

0.28 

92.3 

Carrot,  

12.4 

0.30 

87.6 

Cherries 

25  15 

74  85 

Chickens,  

22.7 

77.3 

Codfish,  

20 

80 

2.86 

97.14 

Eggs,  whites,   

20 

80 

,  yolk,  

46.23 

53.77 

Lard,  hog's   .  .                   . 

100 

79  098 

Milk,  cow's,  .  .            .       .  . 

1298 

87.02 

Oats,  

79  2 

40  154 

1.742 

20.8 

Oatmeal,  

93.4 

6.6 

Olive-oil,  

100 

77.50 

Oysters,  .  . 

12  6 

87.4 

Peaches,  .  

19.76 

80.24 

Pears,  

16.12 

83.88 

Peas,  

84 

35.743 

16 

28.90 

71.10 

Potatoes,  

24.1 

10.604 

0.3615 

75.9 

Rye,  

83.4 

38.530 

1.417 

16.6 

Suet,  mutton,  

100 

78996 

82 

3644 

18 

852 

375 

14.8 

Sugar,  maple,  

42  1 

42  5 

4088 

75 

3  2175 

0  1275 

925 

Veal,  roasted,   

52  52 

14  70 

Wheat,  

85  5 

39  415 

1  966 

14.5 

Note.     Let  the  pupil  mention  those  articles  of  food  that  are  most  mitri 
tious,  from  a  review  of  this  table,  and  the  last  four  paragraphs. 


HYGIENE    OF    THE    DIGESTIVE    ORfiANS. 

^%&UZOB. 

293.  Those  articles  that  do  not  coiitainJjSp^'^n'tial  ele- 
ments of  the  system  should  not  be  used  as  exclusive  articles 
of  diet.     This  principle  has  been,  and  may  be  illustrated  by 
experiment.     Feed  a  dog  with  pure  sugar,  or  olive-oil,  (arti- 
cles that  contain  no  nitrogen,)  for  several  weeks,  and  the  evil 
effects  of  non-nitrogenous  nutriment  will  be  manifested.     At 
first,  the  dog  will  take  his  food  with   avidky,  and  seem  to 
thrive   upon  it ;  soon  this  desire  for  food  will  diminish,  hia 
body  emaciate,  his  eye  become  ulcerated,  and  in  a  few  weeks 
he  will  die  ;  but  mix  bran  or  sawdust  with  the  sugar  or  oil, 
and  the  health  and  vigor  of  the  animal  will  be  maintained  for 
months.     A  similar  phenomenon  will  be  manifested,  if  grain 
only  be  given  to  a  horse,  without  hay,  straw,  or  material  of 
like  character.     (Appendix  H.) 

294.  Some  articles  of  food  contain  the  elements  of  chyle 
in  great  abundance,  yet  afford  but  little  nutriment,  because 
they  are  difficult  of  digestion  ;  while  other  articles  contain  but 
a  small  quantity  of  these  elements,  and  afford  more  nourish- 
ment, because  they  are  more  easily  affected  by  the  digestive 
process. 

295.  The  following  table  exhibits  the  general  results  of 
experiments  made  on  Alexis  St.  Martin,  by  Dr.  Beaumont, 
when  he  endeavored  to  ascertain  the  time  required  for  the 
digestion  of  different  articles  of  food.*     The  stomach  of  St. 
Martin  was  ruplured   by  the   bursting  of  a  gun.     When  he 
recovered  from  the  effects  of  the  accident  under  the  surgical 
care  of  Dr.  Beaumont,  the  stomach  became  adherent  to  the 


*  The  time  required  for  the  digestion  of  the  different  articles  of  food 
might  vary  in  other  pers-jns ;  and  would  probably  vary  in  the  same 
individual  at  different  periods,  as  the  employment,  health,  season,  &c, 
exert  a  modifying  influence. 

293.  How  has  the  effect  of  non-nitrogenous  nutriment  been  illustrated  1 
294.  Why  do  some  articles  of  food  that  contain  the  elements  of  chyle  afford 
but  little  nutriment  ?  Why  do  articles  that  contain  a  small  quantity  of  these 
elements  afford  more  nourishment?  295.  How  was  the  time  reouired  foi 
digest  ing  different  n.-ticles  of  food  ascertained  ? 
10  * 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


TABLE, 

SHOTTING    THE   MEAN   TIME   OF   DIGESTION   OF  THE  DIFFERENT 
ARTICLES   OF  DIET. 


Articles. 

Prepara- 
tion. 

Time 

Articles. 

Prepara- 
tion. 

Tima 

Apples,  sour,  hard,  .  . 

Raw, 
Raw 

h.m. 
2  50 
2 

Meat  hashed  with    ) 

Warm'd, 

h.m. 
2  30 

Raw 

1  30 

Milk,  ....'.'.'.      . 

Boiled, 

2 

Broiled, 

3 

Raw, 

?,  15 

Beans,  pod,  

Boiled, 

2  30 
3 

Mutton,  fresh   .  .  .  . 

Roasted, 
Broiled 

3  15 
3 

Roasted 

3  30 

* 

Boiled 

3 

>  dr}, 
steak,  

Broiled, 
Boiled 

3 
3  36 

Oysters,  fresh    .  .  .  . 

Raw, 
Roasted 

2  55 
3  15 

Boiled 

3  10 

.  •  •  • 

Stewed 

3  30 

.          fresh,  lean,  .  .  . 

Fried,  ' 

4 

Parsnips,  .  .         .  .  . 

Boiled, 

2  30 

—  —  old,  hard,  salted 

Boiled, 

4  15 

Pig,  sucking  

Roasted, 

2  30 

Beets,    

Boiled, 

3  45 

Pigs'  feet,  soused,  .  . 

Boiled, 

1 

Bread,  wheat,  fresh,  . 

Baked, 
Baked, 

3  30 
3  15 

Pork,  fat  and  lean,  . 
,  recently  salted, 

Roasted, 
Boiled, 

5  15 

4  30 

Butter 

Melted 

3  30 

Fried 

4  15 

Raw 

2  30 

' 

Broiled, 

3  15 

Raw 

2 

' 

Raw 

3 

,  TII      imcgar, 

Boiled, 

4  30 

steak,  

Broiled, 

3  15 

Cake   sponge 

Baked, 

2  30 

Potatoes,  Irish,  .  . 

Boiled, 

3  30 

Boiled 

3  15 

Baked 

2  30 

Catfish,  

Fried, 

3  30 

Rice,    

Boiled, 

1 

Raw 

3  30 

Boiled, 

1  45 

Chicken,  full-grown,  . 
Codfish,  cured,  dry,  .  . 
Corn,  green,  &  beans, 
bread,    

Fricas'd, 
Boiled, 
Boiled, 
Baked, 

2  45 
2 
3  45 
3  15 

Salmon,  salted,  .  .  .  . 
Sausage,  fresh,  .  .  .  . 
Soup,  beef,  vegeta-  ) 
bles,  and  bread,     ) 

Boiled, 
Broiled, 

Boiled, 

4 
3  20 

4 

Baked, 

3 

Boiled, 

3 

Custard 

Baked 

2  45 

,  mutton   .... 

Boiled, 

3  30 

Dumpling,  apple,  .  .  . 
Ducks,   domesticated, 

..     TirjlfJ 

Boiled, 
Roasted, 

3 
4 

4  30 

,  oyster,  
Suet,  beef,  fresh,  .  . 

Boiled, 
Boiled, 
Boiled 

3  30 
5  30 
4  30 

Boiled 

3  30 

Tapioca,  

Boiled, 

2 

hard, 
Boiled 

3 

Tripe,  soused,  .  .  .  . 
Trout,  salmon,  fresh, 

Boiled, 
Boiled, 

1 

1  30 

Iorv 

< 

Fried 

3  30 

Raw 

2 

rated                          C 

Roasted, 

2  30 

Fried 

3  30 

Boiled 

2  25 

Boiled 

4 

wild 

Roasted 

2  18 

ow  ,    om    .     ,  .  . 

4 

Boiled 

3  30 

Roasted, 

2  30 

Veal   fresh      

Broiled, 

4 

Broiled 

2  30 

Fried 

4  30 

Liver,  beef's,  fresh,  .  . 

Broiled, 

2 

Venison  steak,  .... 

Broiled, 

i  ;« 

HYGIENE    OF    THE    DIGESTIVE    ORGANS.  139 

side,  with  an  external  aperture.  Nature  had  formed  a  kind 
of  valve,  which  closed  the  aperture  from  the  interior,  and  thus 
prevented  the  contents  of  the  stomach  from  escaping ;  but 
on  pushing  it  aside,  the  process  of  digestion  could  be  seen. 
Through  this  opening,  the  appearance  of  the  coats  of  the  stom- 
ach and  food,  at  different  stages  of  digestion,  were  examined. 

296.  In  view  of  this  table,  the  question  may  be  suggested, 
Is  that  article  of  food  most  appropriate  to  the  system  which  is 
most  easily  and  speedily  digested  ?     To  this  it  may  be  replied, 
that  the  stomach  is  subject  to  the  same  law  as  the  muscles 
and  other  organs  ;  exercise,  within  certain  limits,  strengthens 
it.     If,  therefore,  we  always  eat  those  articles   most  easily 
digested,  the  digestive   powers  will   be  weakened  ;  if  over- 
worked, they  will  be  exhausted.     Hence  the  kind  and  amount 
of  food  should  be  adapted  to  the  maintenance  of  the  digestive 
powers,  and  to  their  gradual  invigoration  when  debilitated. 

Observation.  Food  that  is  most  easily  digested  is  not  al- 
ways most  appropriate  to  a  person  convalescing  from  disease. 
If  the  substance  passes  rapidly  through  the  digestive  process, 
it  may  induce  a  recurrence  of  the  disease.  Thus  the  simple 
preparations  which  are  not  stimulating,  as  water-gruel,  are 
better  for  a  sick  person  than  the  more  digestible  beef  and  fish. 

297.  The  question  is  not  well   settled,  whether  animal  or 
vegetable  food  is  best  adapted  to  nourish  man.     There  are 
nations,  particularly  in  the  torrid  zone,  that  subsist,  exclusive- 
ly, on  vegetables  ;  while  those  of  the  frigid  zone  feed  on  fish  01 
animal  food.     In  the  temperate  zone,  among  civilized  nations, 
a  mixed  diet  is  almost  universal.     When  we  consider  the 
organization  of  the  human  system,  the  form  and  arrangement 
of  the  teeth,  the  structure  of  the  stomach  and  intestines,  we 
are  led  to  conclude,  that  both  animal  and  vegetable  food  is 
requisite,  and  that  a  mixed  diet  is  most  conducive  to  strength, 
health,  and  long  life. 

296.  How  is  the  question  answered,  whether  that  article  is  most  appro- 
pnate  to  the  system  which  is  most  easily  digested  ?  Give  observation. 
2^7  What  is  said  jf  the  adaptation  of  animal  and  vegetable  food  to  man  1 


140  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

298.  The  food  should  be  adapted  to  the  distensible  charat 
ter  of  the  stomach  and  alimentary  canal.     The  former  will  be 
full,  if  it  contain  only  a  gill ;  it  may  be   so  distended  as  to 
contain  a  quart.     The  same  is  true  of  the  intestines.     If  the 
food  is  concentrated,  or  contains  the   quantity  of  nutriment 
which  the  system  requires,  in  small   bulk,  the  stomach  and 
intestines  will  need  the  stimulation  of  distention  and  friction, 
which  is  consequent  upon  the  introduction  and  transit  of  the 
innutritious  material  into  and   through  the  alimentary  canal. 
If  the  food  is  deficient  in  innutritious  matter,  the  tendency 
is,  to  produce  an  inactive  and  diseased  condition  of  the  diges- 
tive organs.    For  this  reason,  nutrient  food  should  have  blend- 
ed with  it  innutritious  material.      Unbolted  wheat  bread   is 
more  healthy  than  hot  flour  cakes ;  ripe  fruits  and  vegetables 
than  rich  pies,  or  jellies. 

Observation.  1st.  The  observance  of  this  rule  is  of  more 
importance  to  students,  sedentary  mechanics,  and  those  indi- 
viduals whose  digestive  apparatus  has  been  enfeebled,  than  to 
those  of  active  habits  and  firm  health. 

2d.  The  circumstance  that  different  articles  of  food  contain 
different  proportions  of  waste,  or  innutritious  matter,  may  be 
made  practically  subservient  in  the  following  way :  If,  at  any 
particular  season  of  the  year,  there  is  a  tendency  to  a  diarrhoea, 
an  article  that  contains  a  small  proportion  of  waste  should  be 
selected  for  food ;  but,  if  there  is  a  tendency  to  an  inactive 
or  costive  condition  of  the  intestinal  canal,  such  kinds  of  food 
should  be  used  as  contain  the  greatest  proportion  of  waste,  as 
such  articles  are  most  stimulating  to  the  digestive  organs,  and, 
consequently,  most  laxative. 

299.  In  the  selection  of  food,  the  influence  of  season  and 
climate  should  be  considered.     Food  of  a  highly  stimulating 
character  may  be  used  almost  with  impunity  during  the  cold 

298.  What  is  said  of  the  distensible  character  of  the  stomach  and  alimenta 
tiiry  canal  /  What  is  the  effect  of  eating  highly  concentrated  food  ?  Why  is 
the  unbolted  wheat  bread  more  healthy  than  flour  cakes  1  Give  observation  1st. 
Observation  2d.  299.  What  kind  of  food  is  adapted  to  cold  weather  ?  To 
iva.-  n  wo.ither  ? 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  141 

weather  of  a  cold  climate  ;  but  in  the  warm  season,  and  in  a 
warm  climate,  it  would  be  veiy  deleterious.  Animal  food, 
being  more  stimulating  than  vegetable,  can  be  eaten  in  the 
winter  but  vegetable  food  should  be  used  more  freely  in  the 
spring  and  summer. 

300.  The  influence  of  food  on  the  system  is  modified  by 
the  age  of  the  individual.     The  organs  of  a  child  are  more 
sensitive  and  excitable  than  those  of  a   person  advanced  in 
years.     Therefore  a  vegetable  diet  would  be  most  appropriate 
for  a  child,  while  stimulating  animal  food  might  be  conducive 
to  the  health  of  a  person  advanced  in  life. 

Observation.  When  the  digestive  organs  are  highly 
impressible  or  diseased,  it  is  very  important  to  adopt  a 
nutritious,  unstimulating,  vegetable  diet,  as  soon  as  the  warm 
season  commences. 

301.  Habit  is  another  strong  modifying  influence.      If  n 
person  has  been  accustomed  to  an  animal  or  vegetable  diet, 
and  there  is  a  sudden  change  from  one  to  the  other,  a  diseased 
condition  of  the  system,  particularly  of  the  digestive  apparatus, 
usually  follows.     When  it  is  necessary  to  change  our  manner 
of  living,  it  should  be  done  gradually.* 

302.  Some  temperaments  require    more   stimulating  food 
than  others.     As  a  general  rule,  those  persons  whose  sensa- 
tions are  comparatively  obtuse,  and  movements  slow,  will  be 
benefited   by  animal   food ;    while    those    individuals  whose 
constitutions  are  highly  impressible,  and  whose  movements 
are  quick  and  hurried,  require  a  nutritious  and  unstimulat- 
ing vegetable  diet. 


*  The  system  is  gradually  developed,  and  all  changes  of  food, 
appaul,  labor,  exercise,  or  position,  should  be  gradual.  Even  a  change 
from  a  bad  to  a  good  habit,  on  this  principle,  should  be  gradual. 


300.  What  kinds  of  food  are  appropriate  to  old  age?  Why?  What 
kinds  to  childhood?  Why?  301.  What  is  the  effect  when  there  is  a 
sudden  change  from  a  vegetable  to  an  animal  diet?  How  should  all 
changes  of  the  system  be  made  ?  302.  Do  different  temperaments  require 
different  kinds  of  food  ?  What  general  rule  is  given  ? 


142  ANATOMY,    PHYSIOLOGY,  AND    HTGIENE. 


CHAPTER     XVI. 

HYGIENE    OF    THE    DIGESTIVE    ORGANS,    CONTINUED, 

303.  The  MANNER  in  which  food  should  be  taken  is  of  much 
practical  importance  ;  upon  it  the  health  of  the  digestive  organs 
measurably  depends.       But  few  circumstances    modify  the 
proper  manner  of  taking  food,  or  should  exercise  any  con 
trolling  influence. 

304.  Food  should  be  taken  at  regular  periods.     The  inter- 
val between  meals  should  be  regulated  by  the  character  of  the 
food,  the  age,  health,  exercise,  and  habits  of  the  individual. 
The  digestive   process    is    more   energetic  and  rapid  in  the 
young,  active,  and  vigorous,  than   in  the  aged,  indolent,  and 
feeble ;  consequently,  food  should   be  taken  more  frequently 
by  the  former  than  by  the  latter  class. 

305.  In  some  young  and  vigorous  persons,  food  may  be 
digested   in  one  hour ;  in  other  persons,  it  may  require  four 
hours  or  more.     The  average  time,  however,  to  digest  an  ordi- 
nary meal,  will  be  from  two  to  four  hours.     In  all  instances, 
the  stomach  will  require  from  one  to  three  hours  to  recruit 
its   exhausted  powers   after   the    labor  of  digesting  a  meal 
before  it  will  again  enter  upon  the  vigorous  performance  of 
its  duties. 

306.  Food  should  not  be  taken  too  frequently.     If  food  is 
taken  before  the  stomach  has  regained  its  tone  and  energy  by 
repose,  the  secretion  of  the  gastric  juice,  and  the  contraction 

303.  Why  is  it  important  that  we  regard  the  manner  of  taking  our  food  ? 
304.  How  should  the  intervals  between  meals  be  regulated?  305.  What  is 
the  average  time  required  to  digest  an  ordinary  meal  ?  306.  Why  shouJ3 
not  food  be  taken  too  frequently? 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  113 

of  the  muscular  fibres,  will  be  imperfect.  Again,  if  food  is 
taken  before  the  digestion  of  the  preceding  meal  has  been 
completed,  the  effects  will  be  still  worse,  because  the  food 
partially  digested  becomes  mixed  with  that  last  taken.  There 
fore  the  interval  between  each  meal  should  be  long  enough 
for  the  whole  quantity  to  be  digested,  and  the  time  of  repose 
should  be  sufficient  to  recruit  the  exhausted  organs.  The 
feebler  the  person  and  the  more  debilitated  the  stomach,  the 
more  important  to  observe  the  above  directions. 

Observation.  In  the  feeding  of  infants,  as  well  as  in 
supplying  food  to  older  children,  the  preceding  suggestions 
should  always  be  regarded.  The  person  who  has  been  con- 
fined by  an  exhausting  sickness,  should  most  scrupulously 
regard  this  rule,  if  he  wishes  to  regain  his  strength  and  flesh 
with  rapidity.  As  the  rapidity  of  the  digestive  process  is  less 
in  students  and  individuals  who  are  engaged  in  sedentary 
employments,  than  in  stirring  agriculturists,  the  former  class 
are  more  liable  to  take  food  too  frequently  than  the  latter, 
while  its  observance  is  of  greater  importance  to  the  sedentary 
artisan  than  to  the  lively  lad  and  active  farmer. 

307.  Food  should  be  well  masticated.     All  solid  aliments 
should  be  reduced  to  a  state  of  comparative  fineness,  by  the 
teeth,  before  it  is  swallowed ;  the  gastric  fluid  of  the  stomach 
will  then  blend  with  it  more  readily,  and  act  more  vigorously 
in  reducing  it  to  chyme.     The   practice  of  swallowing  solid 
food,   slightly   masticated,   or  "  bolting "  it  down,  tends    to 
derange  the  digestive  process  and  impair  the  nutrition  of  the 
system. 

308.  Mastication  should  be  moderate,  not  rapid.     In  mas- 
ticating food,  the  salivary  glands  are  excited  to  action,  and 
some  time  must  elapse  before  they  car  secrete  saliva  in  sufn- 

What  persons  would  be  benefited  by  obsrrrin^  the  preceding  re- 
marks ?  307.  Why  should  food  be  well  masticated  ?  What  is  the  effect 
of  "  bolting  down  "  food  ?  308.  How  should  mastication  be  performed  f 
Why? 


144  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

cient  quantities  to  moisten  it.  If  the  aliment  is  not  supplied 
with  saliva,  digestion  is  retarded ;  besides,  in  rapid  eating, 
more  food  is  generally  consumed  than  the  system  demands, 
or  can  be  easily  digested.  Laborers,  as  well  as  men  of  leisure, 
should  have  ample  time  for  taking  their  meals.  Imperfect 
mastication  is  a  prevailing  cause  of  indigestion. 

309.  Food   should  be   masticated  and  swallowed  without 
drink.     As  the  salivary  glands  supply  fluid  to  moisten  the  dry 
food,  the  use  of  tea,  coffee,  water,  or  any  other  fluid,  is  not 
demanded  by  nature's  laws  while  taking  a  meal.     One  objec- 
tion to  "  washing  down  "  the  food  with  drink  is,  the  aliment 
is  moistened,  not  with  the  saliva,  but  with  the  drink.     This 
tends  to  induce  disease,  not  only  in  the  salivary  organs,  by 
leaving   them    in  a  state  of  comparative  inactivity,   but  in 
the    stomach,  by    the    deficiency  of   the  salivary  stimulus. 
Another  is,  large  quantities  of  fluids,  used  as  drinks,  give 
undue  distention  to  the  stomach,  and  lessen  the  energy  of  the 
gastric  juice  by  its  dilution,  thus  retarding  digestion.     Again, 
drinks  taken  into  the  stomach  must  be  removed  by  absorption 
before  the  digestion  of  other  articles  is  commenced. 

Observation.  Were  it  customary  not  to  place  drinks  on  the 
(able  until  the  solid  food  is  eaten,  the  evil  arising  from  drink- 
ing too  much  at  meals  would  be  obviated.  The  horse  is  never 
known  to  leave  his  provender,  nor  the  ox  his  blade  of  grass,  to 
wash  it  down  ;  but  many  persons,  from  habit  rather  than  thirst, 
drink  largely  during  meals. 

310.  The  peculiar  sensation  in  the  mouth  and  fauces,  called 
thirst,  may  not  always  arise   from  the   demand  for  fluids  to 
increase  the  serum  (water)  of  the  blood,  as  in  the  desire  for 
drink  attendant  on  free  perspiration,  for  then,  pure  water  or 
some  diluent  drink  is  absolutely  necessary ;  but  it  may  be  the 

Why  should  all  persons  ha>  e  ample  time  for  eating  ?  309.  Why  are 
drinks  not  necessary  while  masticating  food?  Give  the  objections  to 
'washing  down"  food.  What  observation  relative  to  drink?  310.  Does 
ihe  sensation  of  thirst  always  arise  from  a  real  want  of  the  system  ? 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  145 

result  of  fever,  or  local  disease  of  the  parts  connected  with 
the  throat.  In  many  instances,  thirst  may  be  allayed  by  chew 
ing  some  hard  substance,  as  a  dry  cracker.  This  excites  a 
secretion  from  the  salivary  glands,  which  removes  the  disa- 
greeable sensation.  In  thirst,  attendant  on  a  heated  condition 
of  the  system,  this  practice  affords  relief,  and  is  safe ;  while 
the  practice  of  drinking  large  quantities  of  cold  fluids,  in 
unsafe,  and  should  never  be  indulged. 

311.  Food  or  drink  should  not   be  taken  when  very  hot. 
When  food  or  drink  is  taken  hot,  the  vessels  of  the  mucous 
membrane  of  the  gums,  mouth,  and  stomach  are  unduly  stim- 
ulated for  a  short  time  ;    and   this  is  followed  by  reaction, 
attended  by  a  loss  of  tone,  and  debility  of  these  parts.     This 
practice  is  a  fruitful  cause  of  spongy  gums,  decayed  teeth, 
sore  mouth,  and  indigestion. 

312.  Food  or  drink  should   not  be  taken  very  cold.     If 
a  considerable  quantity  of  very  cold  food  or  liquid  be  taken 
immediately  into  the  stomach,  the  health  will  be  endangered, 
and  the  tone  of  the  system  will  be  impaired,  from  the  sudden 
abstraction  of    heat  from   the    coats  of   the    stomach,   and 
from  surrounding  organs,  to  impart  warmth  to  the  cold  food 
or  drink.     This  arrests  the  digestive  process,  and  the  food  is 
retained  in  the  stomach  too  long,  and  causes  oppression  and 
irritation.     Consequently,  food  and  drink  that  are  moderately 
heated  are  best  adapted  to  the  natural  condition  of  the  diges- 
tive apparatus. 

Observation.  Food  of  an  injurious  quality,  or  taken  in  an 
improper  manner,  affects  the  inferior  animals  as  well  as  man. 
The  teeth  of  cows  that  are  closely  penned  in  cities,  and  are 
fed  on  distillery  slops,  or  the  unhealthy  slops  and  remnants 
of  kitchens,  decay  and  fall  out  in  about  two  years.  Can  the 
milk  of  such  diseased  animals  be' healthy  —  the  proper  nour- 
ishment for  children  ? 

Give  instances  when  it  does  and  when  it  does  not.     311.  Why  should  not 
food  or  drink  be  taken  hot  ?     312.   Why  should  they  not  be  taken  cold  ? 
SLow  some  of  the  effects  of  improper  food  upon  the  inferior  animals 
I.! 


146  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

313.  The  CONDITION  of  the  system  should  be  regarded  when 
food  is  taken.     This   is  necessary,  as  the  present  and  ulterior 
condition  of  the  digestive  apparatus  is  strongly  influenced  by 
the  state  of  the  other  organs  of  the  system. 

314.  Food  should  not   be  taken  immediately  after  severe 
exertion,  either  of  the  body  or   mind.      For   all    organs    in 
action  require  and  receive  more  blood  and  nervous  fluid,  than 
when  at  rest.     This  is  true  of  the  brain,  muscles,  and  vo- 
cal organs,  when  they  have   been  actively  exercised.     The 
increased  amount  of   fluid,  both  sanguineous  and    nervous, 
supplied  to  any  organ  during  extra  functional  action,  is  ab- 
stracted from  other  parts  of  the  system.     This  enfeebles  and 
prostrates  the  parts  that  supply  the  blood  and  nervous  fluid  to 
the  active  organ.     Again,  when  any  organ  has  been  in  vigor- 
ous action  for  a  few  hours,  some  time  will  elapse  before  the 
increased  action  of  the  arteries  and  nerves  abates,  and  a  due 
supply  of  fluids  is  transmitted  toother  organs,  or  an  equilibrium 
of  action  in  the  system  is  reestablished. 

315.  Thus  food  should   not    be  taken    immediately  after 
severe  mental  labor,  protracted  speaking,  continued   singing, 
or  laborious  manual  toil;  as  the  digestive  organs  will  be  in  a 
state  of  comparative  debility,  and  consequently  unfit  to  digest 
food.     From  thirty  to  sixty  minutes  should  elapse,  after  the 
cessation  of  severe  employment,  before  food  is  taken.     This 
time  may  be  spent  in  cheerful  amusement  or  social  conversa- 
tion. 

Observation.  The  practice  of  students  and  accountants 
going  immediately  from  severe  mental  labor  to  their  meals, 
is  a  pernicious  one,  and  a  fruitful  cause  of  indigestion  and 
mental  debility.  The  custom  of  farmers  and  mechanics 


313.  Should  the  condition  of 'the  system  be  regarded  in  taking  food? 
314.  When  should  food  not  be  taken?  Why?  What  is  the  result  when 
an  organ  has  been  in  vigorous  action  ?  315.  After  the  cessation  of  severe 
to;M  how  much  time  should  expire  before  eating  ?  What  is  one  cause  of 
Indigestion  among  students  and  accountants  ? 


HYGIENE    OF    THE    DIGESTIVE    OKGAJMS.  147 

hurrying  from  their  toil  to  the  dinner-table,  does  much  to 
cause  dyspepsia  and  debility  among  these  classes  in  com- 
munity. 

316.  Severe  mental  or  manual  toil  should  not  be  entered 
upon  immediately  after  eating.     As   there   is  an  increased 
amount  of  blood  and  nervous  fluid  supplied  to  the  stomach 
and  alimentary  canal  during  the  digestion  of  food,  a  deficiency 
exists  in  other  organs.     This  is  evinced  by  a  slight  paleness 
of  the  skin,  and  a  disinclination  to  active  thought  and  exercise. 
Under  such  circumstances,  if  either  the  mind,  vocal  organs, 
or  muscles  are  called  into  energetic  action,  there  will  be  an 
abstraction    of  the  necessary   amount    of    blood    and    ner- 
vous fluid  from   the  stomach,  and    the  process  of  digestion 
will  be  arrested.     This  will  not  only   cause  disease  of  the 
digestive  organs,  but  chyle  will  not  be  formed,  to  nourish  the 
system. 

Illustration.  An  English  gentleman  fed  two  dogs  upon 
similar  articles  of  food.  He  permitted  one  to  remain  quiet  in 
a  dark  room  ;  the  other  he  sent  in  pursuit  of  game.  At  the 
expiration  of  one  hour,  he  had  both  killed.  The  stomach  of 
the  dog  that  had  remained  quiet  was  nearly  empty.  The 
food  had  been  properly  changed  and  carried  forward  into  the 
alimentary  canal.  In  the  stomach  of  the  dog  that  had  used 
his  muscles  in  chasing  game,  the  aliment  remained  nearly 
unaltered. 

317.  The  same  principle  may  be  applied  to  the  action  of 
the  organs  of  man.     If  his  mind  or   muscles   act   intensely 
soon  after  eating,  the  stomach  will  not  be  sufficiently  stimu- 
lated by  blood  and  nervous  fluid  to  change  the  food  in  a 
suitable  period.     The  Spanish  practice  of  having  a  "  siesta," 
or  sleep  after  dinner,  is  far  better  than  the  custom   of  the 

316.  Why  should  not  severe  manual  or  mental  exertion  be  made  imme- 
diately after  eating  ?  State  the  illustration.  317.  May  this  principle  bo 
applied  to  the  action  of  the  human  stomach  ?  What  is  said  of  the  Spanish 
custom  of  resting  after  dinner  ? 


148  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

Angle-Saxon  race,  who  hurry  from  their  meals  to  the  field, 
shop,  or  study,  in  order  to  save  time,  which,  in  too  main 
instances,  is  lost  by  a  sense  of  oppression  and  suffering  which 
*oon  follows. 

318.  In  some  instances  of  good  health,  the  infringement  of 
this  organic  law  may  seem  to  pass  with  impunity,  but  Nature, 
though  lenient,  sooner  or  later  asserts  her  claims.     The  prac- 
tice of  the  Spaniard   may  be  improved  by  indulging,  for  an 
hour  before  resuming  toil,  in  moderate  exercise  of  the  muscu- 
lar  system,   conjoined    with   agreeable   conversation   and   a 
hearty  laugh,  as  this  facilitates  digestion,  and  tends  to  "  shake 
the  cobwebs  from  the  brain." 

Observation.  No  judicious  teamster  drives  his  animals  as 
soon  as  they  have  swallowed  their  food,  but  gives  them  a 
period  for  repose,  so  that  their  food  may  be  digested,  and 
their  systems  invigorated.  In  this  way,  he  secures  the  greatest 
amount  of  labor  from  his  team. 

319.  The  mind  exerts  an  influence  upon  the  digestive  pro- 
cess. ^  This  is  clearly  exhibited,  when  an  individual  receives 
intelligence  of  the    loss   of  a   friend    or    of   property.     He 
may  at  the  time    be   sitting  before  a  plentiful  board,  with  a 
keen  appetite ;  but  the  unexpected  news  destroys  it,  because 
the  excited  brain  withholds  its  stimulus.     This  shows  the  pro- 
priety of  avoiding   absorbing  topics  of  thought  at  meals,  as 
labored  discussions  and    matters  of   business  ;  but  substitute 
cheerful   and  light  conversation,  enlivening  wit,  humor,  the 
social  intercourse  of  family  and  friends  ;  these  keep  the  brain 
in  action,  but  not  in  toil.     Under   such   circumstances,  the 
blood  and  nervous  fluid  flow  freely,  the  work  of  digestion  is 
readily  commenced,  and  easily  carried  on. 

320.  Indigestion  arising  from  a  prostration  of  the  nervous 
system,  should  be  treated  with  great  care.     The  food  should 

Of  the  Anglo-Saxon  race  ?  318.  How  can  the  Spanish  custom  be  im- 
proved ?  319.  How  is  the  influence  of  the  mind  on  the  digestive  process 
exhibited  ?  What  does  it  show  the  necessity  of  avoiding  ?  320.  How 
should  indigestion  arising  from  nervous  prostration  be  treated  ? 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  I  19 

be  simple,  nutritious,  moderate  in  quantity,  and  taken  at  regu- 
lar periods.  Large  quantities  of  stimulating  food,  frequently 
taken,  serve  to  increase  the  nervous  prostration.  Those 
afflicted  should  exercise  in  the  open  air,  and  engage  in  social 
conversation,  that  the  brain  may  be  excited  to  a  natural  or 
healthy  action-,  in  order  that  it  may  impart  to  the  digestive 
organs  th^  necessary  stimulation. 

321.  Persons  should  abstain  from  eating,  at  least  three 
hours  before  retiring  for  sleep.     It  is  no  unusual  occurrence, 
for  those  persons  who  have  eaten  heartily  immediately  before 
retiring  to  sleep,  to  have  unpleasant  dreams,  or  to  be  aroused 
from   their   unquiet   slumber   by    colic    pains.     In  such  in- 
stances, the  brain  becomes  partially  dormant,  and  does  not 
impart  to  the  digestive  organs  the  requisite  amount  of  nervous 
influence.    The  nervous  stimulus  being  deficient,  the  unchanged 
food  remains  in  the  stomach,  causing  irritation  of  this  organ. 

Illustration.  A  healthy  farmer,  who  was  in  the  habit  of 
eating  one  fourth  of  a  mince  pie  immediately  before  going  to 
bed,  became  annoyed  with  unpleasant  dreams,  and,  among  the 
varied  images  of  his  fancy,  he  saw  that  of  his  deceased  father. 
Becoming  alarmed,  he  consulted  a  physician,  who,  after  a 
patient  hearing  of  the  case,  gravely  advised  him  to  eat  half  of 
a  mince  pie,  assuring  him  that  he  would  then  see  his  grand- 
father. 

322.  WJien  the  general  system  and  digestive  organs  are 
enfeebled,  mild,  unstimulating  food,  in  small  quantities,  should 
be  given.     In  the  instance  of  a  shipwrecked   and   famished 
mariner,  or  a  patient  recovering   from    disease,  but  a  small 
quantity  of  nourishment  should  be  given  at  a  time.    The  reason 
for  this,  is,  that  when  the  stomach  is  weakened   from   want 
of  nourishment,  it  is  as  unfitted  for  a  long  period  of  action  in 

321.  What  is  the  effect  of  eating  immediately  before  retiring  for  sleep  ? 
How  is  this  illustrated  in  the  case  of  a  healthy  farmer  ?    322.  How  should 
the  food  be  given  when  both  the  digestive  organs  and  general  system  are 
debilitated  ?    Give  the  reason. 
13* 


150  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

digesting  food,  as  the  muscles  are,  under  like  circumstances, 
for  walking.  Consequently,  knowledge  and  prudence  should 
direct  the  administration  of  food  under  these  circumstances. 
The  popular  adage,  that  "  food  never  does  harm  when  there 
is  a  desire  for  it,"  is  untrue,  and,  if  practically  adopted,  may 
be  injurious  and  destructive  to  life. 

Observation.  Liquids  are  rapidly  removed  from  the  stom- 
ach by  absorption.  Hence,  in  cases  of  great  prostration, 
when  it  is  desirable  to  introduce  nutriment  into  the  system, 
without  delay,  the  animal  and  vegetable  broths  are  a  desirable 
and  convenient  form  of  supplying  aliment. 

323.  The  condition  of  the  skin  exercises  an  important  in- 
fluence on  the  digestive  apparatus.     Let  free  perspiration  be 
checked,  either  from  uncleanliness  or  from  chills,  and  it  will 
diminish  the  functional  action   of  the  stomach  and  its  asso- 
ciated    organs.     This   is   one   of  the    fruitful    causes   of  the 
"  liver  and  stomach  complaints  "  among  the  half-clothed  and 
filthy  population  of  the  crowded  cities  and  villages  of  our 
country.      Attention  to  clothing  and  bathing  would  likewise 
prevent   many  of  the  diseases  of  the  alimentary  canal,  called 
"  season  complaints,"  particularly  among  children. 

324.  Restricting  t/ie  movements  of  the  ribs  and  diaphragm 
impairs  digestion.     At   each   full    inspiration,   the  ribs   are 
elevated,  and  the  central  portion  of  the  diaphragm  is  depressed, 
from  one  to  two  inches.     This  depression  is  accompanied  by  a 
relaxation  of  the  anterior  abdominal   walls.     At  each  act  of 
expiration,  the   relaxed  abdominal  muscles  contract,  the  ribs 
are  depressed,  the  diaphragm  relaxes,  and  its  central  parts 
ascend.     These  movements  of  the  midriff  cause  the  elevation 
and  depression   of  the   stomach,  liver,  and  other   abdominal 
organs,  which  is  a  natural  stimulus  of  these  parts. 

In  cases  of  great  prostration,  what  is  recommended  ?  323.  How  ia 
the  influence  that  the  skin  exercises  on  the  digestive  organs  illustrated  ? 
324.  What  effect  on  the  digestive  process  has  the  restriction  of  the  ribs 
and  diaphragm  ? 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  151 

325.  It  is  noted  of  individuals  who  restrain  the  free  move- 
ments of  the  abdominal  muscles  by  tight  dresses,  that  the  tone 
and    vigor   of  the    digestive    organs   are    diminished.      The 
restricted  waist  will  not  admit  of  a  full  and  deep  inspiration  • 
and  so  essential  is  this  to  health,  that  abuse  in  this  respect 
soon  enfeebles  and  destroys  the  functions  of  the  system. 

326.  Pure  air  is  necessary  to   give  a  keen  appetite  and 
vigorous  digestion.     The  digestive  organs  not  only  need  the 
stimulus  of  blood,  but  they  absolutely  need  the  influence  of 
pure  blood,  which  cannot  exist  in  the  system,  except  when  we 
breathe  a  pure  air.     From  this  we  learn  why  those  persons 
who  sleep  in  small,  ill  ventilated    rooms,  have   little   or  no 
appetite  in  the  morning,  and  why  the  mouth  and  throat  are  so 
dry  and  disagreeable.     The  effect  of  impure  blood,  in  dimin- 
ishing the  desire  for  food,  and  enfeebling  the  digestive  organs, 
is  well  illustrated  by  the  following  incidents. 

Illustrations.  1st.  Dr.  Reid,  in  his  work  on  "  Ventilation 
of  Rooms,"  relates  that  an  innkeeper  in  London,  when  he 
provided  a  public  dinner,  always  spread  his  tables  in  an 
under-ground  room,  with  low  walls,  where  the  air  was  con- 
fined and  impure.  He  assigned  as  a  reason  for  so  doing,  that 
his  guests  consumed  only  one  third  as  much  food  and  wine, 
as  if  the  tables  were  laid  in  the  open  air. 

2d.  A  manufacturer  stated  before  a  committee  of  the 
British  Parliament,  that  he  had  removed  an  arrangement  for 
ventilating  his  mill,  because  he  noticed  that  his  men  ate  much 
more  after  his  mill  was  ventilated,  than  previous  to  admitting 
fresh  air  into  the  rooms,  and  that  he  could  not  afford  to  have 
them  breathe  pure  air. 

Observation.  Many  of  the  cases  of  indigestion  among 
clergymen,  seamstresses,  school  teachers,  sedentary  me- 

325.  What  is  observed  of  those  individuals  that  restrict  the  movements 
of  the  abdominal  muscles  ?  326.  Why  is  pure  air  necessary  to  vigorous 
digestion  ?  Give  illustration  1st.  Illustration  2d.  What  is  one  cause  of 
indigestion  among  the  sedentary  class  in  community  ? 


152  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

chanics,  and  factory  operatives,  are  produced  by  breathing 
the  impure  air  of  the  rooms  they  occupy.  These  cases  can 
be  prevented,  as  well  as  cured,  by  proper  attention  to 
ventilation. 

327.  The  position  of  a  person,  in  standing   or   sitting, 
exerts  an  influence  upon  the  digestive  organs.     If  a  person 
lean,  or  stoop  forward,  the  distance  between  the  pelvic  bones 
and  the  diaphragm   is  diminished.      This   prevents   the   de- 
pression of  the  diaphragm,  while  the  stomach,  liver,  pancreas, 
and  other  abdominal  organs,  suffer  compression,  which  induces 
many  severe  diseases  of  these  organs.     As  healthy  and  well- 
developed  muscles  keep  the  spinal  column  in  an  erect  position, 
which  conduces  to  the  health  of  the  organs  of  digestion,  the 
child  should  be  taught  to  avoid  all  positions  but  the  erect,  while 
studying  or  walking.      This  position,  combined  with    unre- 
stricted waists,  will  do  much  to  remove  the  now  prevalent 
disease,  dyspepsia. 

328.  Whatever  kind  of  aliment  is  taken,  it  is  separated 
into  nutriment   and  residuum ;  the  former  of  which  is  con- 
veyed, through  the   medium  of  the  circulation,  to  all  organs 
of  the   system,  and  the   latter,  if  not  expelled,  accumulates, 
causing  headache  and  dizziness,  with  a  general  uneasiness; 
and,  if  allowed  to  continue,  it  lays  the  foundation  of  a  long 
period  of  suffering   and    disease.     For   the    preservation  of 
health,  it  is  necessary  that  there  should  be  a  daily  evacuation 
of  the  residual  matter. 

Observation.  In  chronic  diseases  of  the  digestive  organs, 
very  frequently,  there  is  an  inactive,  or  costive  condition  of 
the  alimentary  canal.  This  may  be  removed  in  many  cases, 
and  relieved  in  all  instances,  by  friction  over  the  abdominal 
organs,  and  by  making  an  effort  at  some  stated  period  each 
day,  (evening  is  best,)  to  evacuate  the  residuum.  In  acute 

327   Why  does  the  position  of  a  person  affect  digestion  ?    328.  Into 
what  are  different  kinds  of  aliment  separated  ? 


HYGIENE    OF    THE    DIGESTIVE    ORGANS.  153 

diseases,  as  fever,  regard  should  be  given  to  regularity  in  re- 
lieving the  intestines  of  residuum.  Attention  to  this  sugges* 
tion  will  in  many  instances  obviate  the  necessity  of  cathartic 
medicine. 

329.  We  would  add,  for  the  benefit  of  those  afflicted  with 
hemorrhoids,  or  piles,  that  the  best  time  for  evacuating  the 
intestinal  canal  would  be  immediately  before  retiring  for  the 
night.     During  the   night,  while   recumbent,  the   protruding 
parts  return  to  their  proper  place,  and  the  surrounding  organs 
acquire  increased  tone  to  retain  them.     The  same  observance 
will  do  much  to  prevent  such  prostrating  diseases.* 

330.  To  recapitulate :  digestion  is  most  perfect  when  the 
action  of  the  cutaneous  vessels  is  energetic ;  the  brain  and 
vocal  organs  moderately  stimulated  by  animated   conversa- 
tion ;   the   blood  well    purified ;    the   muscular   system    duly 
exercised  ;  the  food  of  an  appropriate  quality,  taken  in  proper 
quantities,  at  regular  periods,  and  also  properly  masticated. 


*  The  urinary  organs,  as  well  as  the  intestinal  canal,  should  be 
frequently  and  regularly  evacuated.  Some  most  distressing  and 
frequently  incurable  complaints  are  caused  by  false  customs  and 
false  delicacy  in  this  particular.  Teachers  should  be  particularly 
careful,  and  regard  this  suggestion  in  reference  to  young  pupils. 

8*^0.  Give  the  summary  when  digestion  is  most  perfect. 


154  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


CHAPTER    XVII. 

THE    CIRCULATORY    ORGANS. 

331.  THE  ultimate  object  of  the  food  and  drink  introduced 
into  the  body,  is  to  furnish  material  to  promote  the  growth 
and  repair  the  waste  of  the  organs  of  the  system.     The  for- 
mation of  chyle  (the  nutrient  portion  of  the  food)  has  been 
traced  through  the  digestive  process,  and  its  transfer  into  the 
vein  at  the  lower  part  of  the  neck,  from  which  it  is  conveyed 
to  the  heart;  and,  finally,  in  the  lunifs,  it  assimilates  to  the 
character  of  blood. 

332.  The  BLOOD,  after  standing  a  short  time,  when  drawn 
from  its  vessels,  separates  into  se'rum,  (a  watery  fluid,)  and 
co-ag'u-lum,  (clot.)     This  fluid  is  distributed  to  every  part  of 
the  system.      There  is  no  part  so  minute  that  it  does  no\ 
receive    blood.     The    organs   bynmSch   this    distribution   is 
effected  are  so  connected  that  there  is  properly  neither  begin- 
ning nor  end  ;  but  as  it  respects  their  functions,  they  are  con- 
nected in  a  complete  circle.     From  this  circumstance,  they 
are  called  the  Circulatory  Organs. 

ANATOMY  OF  THE  CIRCULATORY  ORGANS. 

333.  The  CIRCULATORY  ORGANS  are  the  Heart,  Ar'te-ries 
Veins,  and  Cap'il-la-ries. 

334.  The  HEART  is  placed  obliquely,  in 'the  left  cavity  of 
the  chest,  between  the  right  and  left  lung.     Its  ^general  form 

331.  "What  is  the  ultimate  object  of  the  food  ?  332.  Of  what  is  the  blood 
composed  ?  What  is  said  of  the  distribution  of  the  blood  ?  333.  Name 
the  circulatory  organs.  334 — 351.  Give  the  anatomy  of  th#  circulatory 
ornanx.  334.  Describe  the  heart. 


ANATOMY    OF    THE    CIRCULATORY    ORGANS. 


155 


is  that  of  an  inverted  cone,  the  base  of  which  is  directed 
upward  and  backward,  toward  the  right  shoulder,  while  it3 
apex  points  forward  to  the  left  side,  about  three  inches  from 
the  sternum  to  the  space  between  the  fifth  and  sixth  ribs.  Its 
under  side  rests  upon  the  tendinous  portion  of  the  diaphragm. 
The  heart  is  surrounded  by  a  sac,  called  the  per-i-car 'di-um, 
(heart-case.)  The  interior  surface  of  this  membrane  secretes 
a  watery  fluid,  that  lubricates  the  exterior  of  the  heart,  and 
obviates  friction  between  it  and  the  pericardium. 


Fig.  66. 


Fig.  67. 


Fig.  66.  A  front  view  of  the  heart.  1,  The  right  auricle  of  the  heart.  2,  The 
'A ft  auricle.  3,  The  right  ventricle.  4,  The  left  ventricle.  5,  6,  7,  8,  9,  10,  The 
vessels*  through  which  the  blood  passes  to  and  from  the  heart. 

Fig.  67.  A  back  view  of  the  heart.  1,  The  right  auricle  2,  The  left  auricle. 
3,  The  right  ventricle.  4,  Vhe  left  ventricle.  5,  6,  7,  The  vessels  that  carry  the 
blood  to  and  from  the  heart.  9,  10,  11,  The  autrient  vessels  of  the  heart. 

i 

Observation.  In  heaUh,Tfiere  is  usually  about  a  tea-spoon- 
ful of  fluid  in  the  pericardium.  When  these  parts  are  dis- 
eased, it  may  be  thrown  out  more  abundantly,  and  sometimes 


*  All  vessels  that  carry  blood  to  the  heart,  are  called  veins. 
vessels  that  carry  blood  from  the  heart,  are  called  arteries. 


All 


With  what  is  it  surrounded  ?    What  is  its  use  ? 
is  meir.br ane  contain  when  healthy  ? 


How  much  fluid  doeb 


!">(>  AN. ATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

amounts  to  several  ounces,  producing  a  disease  called  dropsy 
of  the  heart.  But  all  the  unpleasant  sensations  in  the  region 
of  the  heart  are  not  caused  by  an  increased  amount  of  fluid  in 
the  pericardium,  as  this  disease  is  not  of  frequent  occurrence. 
335.  The  heart  is  composed  of  muscular  fibres,  that 
traverse  it  in  different  directions,  some  longitudinally,  but 
most  of  them  in  a  spiral  direction.  The  human  heart  is  a 
double  organ,  or  it  has  two  sides,  called  the  right  and  the  left. 
The  compartments  of  the  two  sides  are  separated  by  a  mus- 
cular sep'tum,  or  partition.  Again,  each  side  of  the  heart  is 
divided  into  two  parts,  called  the  Au'ri-cle  (deaf  ear)  and  the 

Veritri-cle. 

Fig.  68. 


Fig.  68.  A  section  of  the  heart,  showing  its  cavities  and  valves.  3,  Th«  right 
.-ttiricle.  4,  The  opening  between  the  right  auricle  and  right  ventricle.  5,  The  right 
ventricle.  6,  The  tricuspid  valves.  7,  The  pulmonary  artery.  9,  The  semilunar 
valves  of  the  pulmonary  artery.  10,  The  septum  between  the  right  and  left  ventricle. 
12,  The  left  auricle.  13,  The  opening  between  the  left  auricle  and  left  ventricle. 
14,  The  left  ventricle.  15,  The  mitral  valves.  16,  The  aorta.  IT,  The  semilunar 
valves  of  the  aorta. 

336.  The  AURICLES  differ  in  *  muscularity  from  the  ventri- 
cles.    Their  walls  are  thinner,  and  of  a  bluish  color.     These 
cavities  are  a  kind  of  reservoir,  designed  to  contain  the  blood 
arriving  by  the  veins. 

337.  The  VENTRICLES  not  only  have  their  walls  thicker 
than  the  auricles,  but  they  differ  in  their  internal  structure. 

335.  Of  what  is  the  heart  composed  ?  Give  its  divisions.  336.  Describe 
f.hp  auricles.  337.  Describe  the  ventricles. 


I! 


ANATOMY    OF    THE    CIRCULATORY    OKOANS.  Iff? 

Prom  the  interior  of  these  cavities  arise  fleshy  columns,  called  - 
co-lum'nce  car'ne-a.     The  walls  of  the  left  ventricle  are  thicker 
and  stronger  than  those  of  the  right. 

338.  The  cavities  in  the  right  side  of  the  heart  are  triangu- 
lar in  shape  ;  those  of  the  left,  oval.     Each  cavity  will  con 
tain  about  two  ounces  of  blood.      Between  the  auricle  and 
ventricle  in  the  right  side  of  the  heart,  there  are  three  folds 
or  doublings,  of  thin,  triangular  membrane,  called  the  tri-cus' 
pid  valves.     Between  the  auricle  and  ventricle  in  the  left  side, 
there  are  two  valves,  called  the  mi'tral.    There  are  seen  pass- 
ing from  the  floating  edge   of  these  valves  to  the   columnse 
carneae,  small  white  cords,  called  chor'd<%   ten'di-nce,  which 
prevent  the  floating  edge  of  the  valve  from  being  carried  into 
the  auricle. 

339.  The  right  ventricle  of  the  heart  gives  rise  to  the  Pul'- 
mo-na-ry  artery ;  tjie  left  ventricle,  to  a  large  artery  called 
the  A-ort'a.     At  the  commencement  of  each  of  these  arteries 
there  are  three  folds  of  membrane,  and  from  their  shape,  they 
are  called  sem-i-lu'nar  valves. 

340.  The  heart  is  supplied  with  arteries  and  veins,  which 
ramify  between  its  muscular  fibres,  through  which  its  nutrient 
blood  passes.     It  has,  likewise,  a  few  lymphatics,  and  many 
small  nervous  filaments  from  the  sympathetic  system  of  nerves. 
This  organ,  in  its  natural  state,  exhibits  but  slight  indications 
of  sensibility,  and  although  nearly  destitute  of  the  sensation  of 
touch,  it  is  yet,  however,  instantly  affected  by  every  painful 
bodily  excitement,  or  strong  mental  emotions, 

Observation.    To  obtain  a  clear  idea  of  the   heart  and  its 
valves,  it  is  recommended   to  examine  this  part  of  an  ox  or 

338.  How  do  the  cavities  in  the  heart  differ  ?  "What  is  found  between 
the  auricle  and  ventricle  in  the  right  side  of  the  heart  ?  How  many  val\  es 
in  the  left  side,  and  their  names  ?  Where  are  the  tendinous  cords,  and 
what  \s  their  use  ?  339.  What  vessels  proceed  from  the  ventricles  ?  What 
•s  3V  d  of  their  valves  ?  340.  With  what  is  the  heart  supplied?  What  is 
-aH  of  its  se»  sibility  ?  How  can  an  idea  of  the  structure  of  the  heart  be 
M-i  ned  ? 

II 


158  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

calf.  In  order  that  each  ventricle  be  opened  without  mutilat 
mg  the  fleshy  columns,  tendinous  cords,  and  valves,  cut  on 
each  side  of  the  septum  parallel  to  it.  This  may  be  easily 
found  between  the  ventricles,  as  they  differ  in  thickness^ 

341.  The  ARTERIES  are  the  cylindrical  tubes  that  convey 
the  blood  from  the  heart  to  every  part  of  the  system.     They 
are  dense  in  structure,  and  preserve,  for  the  most  part,  the 
cylindrical  form,  when  emptied  of  their  blood,  which  is  their 
condition  after  death. 

342.  The   arteries   are   composed    of    three   coats.     The 
external,  or  cellular  coat,  is  firm  and  strong ;  the  middle,  or 
fibrous  coat,  is  composed  of  yellowish  fibres.     This  coat  is 
elastic,  fragile,  and  thicker  than  the  external  coat.     Tts  elas- 
ticity enables  the  vessel  to  accommodate  itself  to  the  quantity 
of  blood  it  may  contain.     The  internal  coat  is  a  thin,  serous 
membrane,  which  lines  the  interior  of  the  artery,  and  gives 
it  the  smooth   polish  which  that  surface  presents.     It  is  con- 
tinuous with  the  lining  membrane  of  the  heart. 

343.  Communications  between  arteries  are  free  and  nu- 
merous.     They   increase   in  frequency  with   diminution   in 
the  size  of  the  branches,  so  that  through  the  medium  of  the 
minute  ramifications,  the  entire  body  may  be  considered  as 
one  circle  of  inosculation.     The  arteries,  in  their  distribution 
through  the  body,  are  enclosed  in  a  loose,  cellular  investment, 
called  a  sheath,  which  separates  them  from  the  surrounding 
tissues. 

344.  The  PULMONARY  ARTERY  commences  in  front  of  the 
origin  of  the  aorta.     It  ascends  obliquely  to  the  under  surface 
of  the  arch  of  the  aorta,  where  it  divides  into  two  branches, 
one  of  which  passes  to  the  right,  the  other  to  the '  left  lung. 
These  divide  and  subdivide  in  the  structure  of  the  lungs,  and 
terminate  in   the  capillary  vessels,  which  form  a  net-work 

341.  What  are  arteries  ?  342.  Give  their  structure.  343.  What  is  said 
of  the  communications  between  the  arteries  ?  In  their  distribution,  ho\v 
are  they  separated  from  the  surrounding  tissues  ?  344.  Describe  the  pul- 
monary artery. 


ANATOMY    OF    THE    CIRCULATORY    ORGANS. 


159 


around  the  air-cells,  and  become  continuous  with  the  minute 
branches  of  the   pulmonary  veins.     This  artery  conveys  the 
impure  blood  to  the  lungs,  and,  with  its  corresponding  veins, 
establishes  the  lesser,  or  pulmonic  circulation. 
Fig.  69. 


Fig.  C9.  t,  The  tracliea.  h,  The  heart,  a,  The  aorta,  p,  The  pulmonary  artery 
1,  The  branch  of  tne  pulmonary  artery  that  divides  in  the  left  lung.  2,  The  branch 
that  divides  in  the  right  lung. 

The  divisions  of  this  artery  continue  to  divide  and  subdivide,  until  they  become 
no  larger  than  hairs  in  size.  These  minute  vessels  pass  over  the  air-cells,  represented 
by  small  dark  points  around  the  margin  of  trie  lungs. 

345.  The  AORTA  proceeds  from  the  left  ventricle  of  the 
heart,  and  contains  the  pure,  or  nutrient  blood.  This  trunk 
gives  off  branches,  which  divide  and  subdivide  to  their  ulti- 
mate ramifications,  constituting  the  great  arterial  tree  which 
pervades,  by  its  minute  subdivisions,  every  part  of  the  animal 
frame.  This  great  artery  and  its  divisions,  with  their  return 
Ing  veins,  constitute  the  greater,  or  systemic  circulation. 

What  does  this  artery  and  its  corresponding  veins  establish  ?  Explain 
fig.  69.  345.  Describe  the  aorta.  What  do  this  artery  and  its  corre- 
sponding veins  constitute  ? 


100        AX  ATOMY,  PHYSIOLOGY,  AND  HYGIE^S. 
Fig.  70. 


Fig.  70.  The  aorta  and  its  branches.  1,  The  commencement  of  tho  aorta. 
2,  The  arch  of  the  aorta.  3,  The  carotid  artery.  4,  The  temporal  artery.  5,  Tho 
subclavian  artery.  6,  The  axillary  artery.  7,  The  brachial  artery.  8,  The  radial 
artery.  9,  The  ulnar  artery.  10,  The  iliac  artery.  11,  The  femoral  artery.  12,  The 
tibial  artery.  13.  The  peroneal  artery. 

346.  The  VEINS  are  the  vessels  which  return  the  blood  to 
the  auricles  of  the  heart,  after  it  has  been  circulated  by  the 

What  does  fig.  70  represent  ?     346.  What  are  the  veins  ? 


ANATOMY    OF    THE    CIRCULATORY    ORGANS.  1G1 

arteries  through  the  various  tissues  of  the  body.  They  are 
thinner  and  more  delicate  in  structure  than  the  arteries,  so 
that  when  emptied  of  their  blood,  they  become  flattened  and 
collapsed.  The  veins  commence  by  minute  radicles  in  the 
capillaries,  which  are  every  where  distributed  through  the 
textures  of  the  body,  and  coalesce  to  constitute  larger  and 
larger  branches,  till  they  terminate  in  the  large  trunks  which 
convey  the  dark-colored  blood  directly  to  the  heart.  In  diam- 
eter they  are  much  larger  than  the  arteries,  and,  like  those 
vessels,  their  combined  area  would  constitute  an  imaginary 
cone,  the  apex  ,of  which  is  placed  at  the  heart,  and  the  base 
at  the  surface  of  the  body. 

347.  Tne   communications   between  the  veins  are    more 
frequent  than  between  the  arteries,  and  take  place  between 
the  larger  as  well  as  among  the  smaller  vessels.     The  office  of 
these  inosculations^  very  apparent,  as  tending  to  obviate  the 
obstructions  to  which  the  veins  are  peculiarly  liable,  from  the 
thinness  of  their  coats,  and  from  inability  to  overcome  great 
impediments  by  the  force  of  their  current.     These  tubes,  as 
well  as  the  arteries,  are  supplied  with  nutrient  vessels,  and  it 
is  to  be  presumed  that  nervous  filaments  from  the  sympathetic 
nerves  are  distributed  to  their  coats. 

348.  The  external,  or  cellular  coat  of  the  veins,  is  dense 
and  firm,  resembling  the  cellular  tunic  of  the  arteries.     The 
middle  coat  is  fibrous,  like  that  of  the   arteries,  but  extremely 
thin.     The  internal  coat  is  serous,  and  also  similar  to  that  of 
the  arteries.     It  is  continuous  with  the  lining  membrane  of  the 
heart  at  one  extremity,  and  with  the  lining  membrane  of  the 
capillaries  at  the  other. 

349.  At  certain  intervals,  the  internal  coat  forms  folds,  or 

Where  do  they  commence  ?  347.  What  is  said  of  their  communica- 
tions ?  What  is  the  apparent  design  of  the  inosculations  of  the  veins ! 
What  vessels  are  distributed  to  the  coats  of  the  veins  ?  348.  Give  the 
structure  of  the  coats  of  the  veins.  349.  How  are  the  valves  in  the 
veins  formed  ? 

14  * 


162 


ANATOMY,    PHYSIOLOGY,  J\ND    HYGIENE. 


duplicatures,  which  constitute  valves.  They  are  generally  com- 
posed of  two  semilunar  folds,  one  on  each  side  of  the  vessel. 
The  free  extremity  of  the  valvular  folds  is  concave,  and 
directed  forward,  so  that  while  the  current  of  blood  sets  toward 
the  heart,  they  present  no  impediment  to  its  free  passage  ;  but 
let  the  current  become  retrograde,  and  it  is  impeded  by  their 
distention.  The  valves  are  most  numerous  in  the  veins  of  the 
extremities,  particularly  the  deeper  veins  situated  between  the 
muscles  ;  but  in  some  of  the  larger  trunks,  and  also  in  some 
of  the  smaller  veins,  no  valves  exist. 

Fig.  71. 


Fig.  71.    A  vein  laid  open  to  snow  the  valves.    1,  The  trunk  of  the  vein,     2,  2,  Its 
ra'ves.    3,  An  opening  of  a  branch  into  the  main  trunk. 

What  is  thoir  use  ?    Where  j».re  they  the  most  numerous  ? 


ANATOMY    OF    ^ME    LfKL'ULATORY    ORGANS. 


350.  The  CAPILLARIES  constitute  a  microscopic  net-work, 
pnd  are  so  distributed  through  every  part  of  the  body  as  to 
render  it  impossible  to  introduce  the  smallest  needle  beneath 
the   skin,   without   wounding   several   of  these   fine  vessels. 
They  are  remarkable  for  the  uniformity  of  diameter,  and  for 
the  constant  divisions  and  communications  which  take  place 
between  them. 

351.  The  capillaries  inosculate,  on  the  one  hand,  with  the 
terminal  extremity  of  the  arteries,  and  on  the  other,  with  the 
commencement  of  the  veins.     They  establish  the  communi- 
cation between  the  termination  of  the  arteries  and  the  begin- 
ning of  the  veins.      The    important  operations  of  secretion 
and  the  conversion  of  the  nutrient  materials  of  the  blood  into 
bone,  muscle,  &c.,  are  performed  in  these  vessels. 


Fig.  72. 


Fig.  73. 


Fig.  72.  An  ideal  view  of  a  portion  of  the  pulmonic  circulation.  1, 1,  A  branch  of 
Mie  artery  that  carries  the  impure  blood  to  the  lungs.  3,  3,  Capillary  vessels.  2,  2,  A 
vein  through  which  red  blood  is  returned  to  the  left  side  of  the  heart. 

Fig.  73.  An  ideal  view  of  a  portion  of  the  systemic  circulation.  1,1,  A  branch 
of  the  aorta.  This  terminates  in  the  capillaries,  (3,  3.)  2,  2,  A  vein  through  which 
the  impure  blood  is  carried  to  the  right  side  of  the  heart. 

350.  What  do  the  capillaries  constitute  ?  For  what  are  they  remark- 
able ?  351.  What  relation  do  they  bear  to  the  arteries  and  veins  ?  What 
important  operations  are  performed  in  these  vessels  ?  What  is  represented 
by  fig.  72?  By  fig.  73? 


164  ANATOMY,  PHYSIOLOGY,  AND  HYGIENE. 


CHAPTER     XVIII. 

PHYSIOLOGY  OF  THE  CIRCULATORY  ORGANS. 

352.  THE  walls  of  all  the  cavities  of  the  heart  are  com- 
posed   of    muscular    fibres,    which    are    endowed    with   tho 
property  of  contracting  and  relaxing,  like  the  musc.es  of  the 
extremities.     The   contraction   and   relaxation   of  the    mus- 
cular  tissue   of    the   heart,    produce   a   diminution   and   en- 
largement of  both  auricular  and  ventricular  cavities.     The 
auricles  contract  and   dilate  simultaneously,  and   so  do  the 
ventricles ;  yet  the  contraction  and  dilatation  of  the  auricles  do 
not  alternate  with  the  contraction  and  dilatation  of  the  ventri- 
cles, as  the  dilatation  of  the  one  is  not  completed  "before  the' 
contraction  of  the  other  commences.     The  dilatation  of  the 
ventricles  is  termed  the  di-as'to-le  of  the  heart ;  their  con- 
traction, its  sys'to-le. 

353.  The  ventricles  contract  quicker  and  more    forcibly 
than  the  auricles,  and  they  are  three  times  longer  in  dilating 
than   contracting.     The    walls   of  the    right   ventricle,  being 
thinner  than  the  left,  are  more  distensible,  and  thus  this  cavity 
will  contain  a  greater  amount  of  blood.     This  arrangement 
adapts  it  to  the  venous  system,  which  is  more  capacious  than 
the  arterial.     The  thicker  and  more   powerful  walls  of  the 
left  ventricle  adapt  it  to  expel  the  blood  to  a  greater  distance. 

354.  The  valves  in  the  heart  permit  the  blood  to  flow  from 
the    auricles  to  the  ventricles,  but  prevent  its  reflowing.     The 
valves   at  the  commencement  of  the  aorta  and    pulmonary 

352 — 366.  (rive  the  physiology  of  the  circulatory  organs.  352.  What  do 
the  contraction  and  relaxation  of  the  muscular  walls  of  the  heart 
produce  ?  How  do  the  auricles  and  ventricles  contract  and  dilate  ? 
353.  What  is  said  of  the  contraction  and  dilatation  of  the  ventricles  in 
the  heart  ?  How  is  the  right  ventricle  adapted  to  its  function  ?  How 
the  left  ?  354.  What  is  the  use  of  the  valves  in  the  heart  ?  Those  of 
the  aorta  and  pulmonary  artery  ? 


PHYSIOLOGY    OF    THE    CIRCULATORY    ORGANS. 


165 


artery,  permit  the  blood  to  flow  from  the  ventricles  into  these 
vessels,  but  prevent  its  returning. 

355.  The  function  of  the  different  parts  of  the  heart 
will  be  given,  by  aid  of  fig.  74.  The  blood  passes  from  the 
right  auricle  (3)  into  the  right  ventricle,  (5,)  and  the  tricuspid 
valves  (6)  prevent  its  reflux ;  from  the  right  ventricle  the 
blood  is  forced  into  the  pulmonary  artery,  (7,)  through  which 
it  passes  to  the  lungs.  The  semilunar  valves  (9)  prevent 
this  circulating  fluid  returning  to  the  ventricle.  The  blood, 
while  passing  over  the  air-cells  in  the  lungs,  in  the  minute 
divisions  of  the  pulmonary  artery,  is  changed  from  a  bluish 
color  to  a  bright  red.  It  is  then  returned  to  the  left  auricle 
of  the  heart  by  the  pulmonary  veins,  (11,  11.) 


14 


Fig.  74.  1,  The  descending  vena  cava,  (vein.)  2,  The  ascending  vena  cava,  (vein.) 
8,  The  right  auricle.  4,  The  opening  between  the  right  auricle  and  the  right  ventri- 
cle. 5,  The  right  ventricle.  6,  The  tricuspid  valves.  7,  The  pulmonary  artery. 

8,  8,  The  branches  of  the  pulmonary  artery  that  pass  to  the  right  and  left  lung. 

9,  The  semilunar  valves  of  the  pulmonary  artery.     10,  The  septum  between  the  two 
ventricles  of  the  heart.     11,  11,  The  pulmonary  veins.     12,  The  left  auricle.     13,  The 
opening  between  the  left  auricle  and   ventricle.     14,  The  left  ventricle.     15,  The 
mitral  valves.     16,  16,  The  aorta.     17,  The  semilunar  valves  of  the  aorta. 

355.  Describe  the  course  of  the  blood  from  the  right  auricle  in  the  heart 
U>  the  lungs. 


166  ANATOMY,    PHYSlOLCHj-S ,   AND    HYGIENE. 

Observation.  If  the  blood  is  not  changed  in  the  lung«,  it 
will  not  flow  to  the  pulmonary  veins.  This  phenomenon  is 
seen  in  instances  of  death  from  drowning,  strangling,  carbonic 
acid,  &c.  The  same  is  true,  but  in  a  less  degree,  of  indi- 
viduals whose  apparel  is  tight,  as  well  a~>  of  those  who  breathe 
impure  air,  or  have  diseased  lungs. 

356.  The  left  auricle,  (12,)  by  its  contraction,  forces  th^ 
blood  into  the  left  ventricle,  (14.)    The  mitral  valves  (15)  pre 
vent  its  reflowing.     From  the  left  ventricle  the  blood  is  forcer 
into  the  aorta,  ( 16,)  through  which,  and  it*  subdivisions,  it  L 
distributed  to  every  part  of  the  system.     The  semilunar  valve 
(17)  prevent  its  returning. 

Observation.  The  parts  of  the  circulatory  organs  mosl 
liable  to  disease  are  the  valves  of  the  heart,  particularly  th« 
mitral>-  When  these  membranous  folds  become  ossified  o' 
ruptured,  the  blood  regurgitates,  and  causes  great  distress  ii 
breathing.  The  operations  of  the  system  are  thus  disturbed 
as  the  movements  of  the  steam  engine  would  be  if  its  valve 
were  injured,  or  did  not  play  freely. 

357.  The  difference  between  the  functions  of  the  pulmo- 
nary artery  and  aorta  is,  the*  former  communicates  with  the 
right  ventricle  of  the  heart,  and  distributes  only  impure  blooo 
to  the  lungs ;  the  other  connects  with  the  left  ventricle  of  thr 
heart,  and  distributes  pure  blood  to  the  whole  body,  the  lung? 
not  excepted.     At  the  extremity  of  the  divisions  of  the  aorta, 
as  well  as  the  pulmonary  artery,  are  found  capillary  vessels. 
This  curious  net-work  of  vessels  connects  with  the  minute 
veins  of  the  body,  which  return  the  blood  to  the  heart. 

Observation.     The  function  of  the  veins  of  the  systemic 


What  is  the  effect  when  the  blood  is  not  changed  in  the  lungs  ? 
356.  Describe  the  circulation  of  the  blood  from  the  left  auricle  to  th; 
general  system.  What  part  of  the  circulatory  organs  is  most  liable  to 
disease  ?  What  is  the  effect  when  the  valves  are  diseased  ?  357.  Give  the 
difference  in  the  functions  of  the  pulmonary  artery  and  aorta.  Show  the 
relation  between  the  functions  of  the  arteries  and  veins  both  of  the  p:i_ 
monic  and  systemic  circulation. 


. 
PHYSIOLOGY    OF    THE    CIRCULATORY    ORGANS.  167 

circulation  is  similar  to  the  office  of  the  arteries  in  the  lungs, 
and  that  the  veins  of  the  pulmonic  circulation  transmit  to  the 
heart  the  pure;  or  nutrient  blood,  and  thus  supply  the  arteries 
of  the  general  system  with  assimilating  fluid. 

358.  The  veins  that  receive  the  blood  from  all  parts  of  the 
body,  follow  nearly  the  same  course  as  the  arteries.     The 
myriads  of  these  small  vessels  beneath  the  skin,  and  others 
that  accompany  the  arteries,  at  last  unite  and  form  two  large 
trunks,  called  ve'na  ca'va  as-cend'ens,  and  de-scend'ens. 

Observation.  A  peculiarity  is  presented  in  the  veins  which 
come  from  the  stomach,  spleen,  pancreas,  and  intestines. 
After  forming  a  large  trunk,  they  enter  the  liver,  and  ramify 
like  the  arteries,  and  in  this  organ  they  again  unite  into  a 
trunk,  and  enter  the  ascending  vein,  or  cava,  near  the  heart. 
This  is  called  the  portal  circulation. 

359.  The  ventricles  of  the  heart  contract,  or  the  "  pulse  " 
beats,  about  seventy-five  times  every  minute,  in  adults ;  in 
infants,  more   than  a  hundred  times  every  minute  ;    in  old 
persons,   less   than   seventy-five   times   every   minute.     The 
energy  of  the  contraction  of  this  organ  varies  in  different 
individuals  of  the  same  age.     it  is  likewise  modified  by  the 
health  and  tone  of  the  system.     It  is  difficult  to  estimate  the 
muscular  power  of  the  heart ;  but,  comparing  it  with  other 
muscles,   and   judging  from  the   force  with  which  blood   is 
ejected  from  a  severed  artery,  it  must  be  very  great. 

Observation.  The  phenomenon  known  under  the  name  of 
pulse,  is  the  motion  caused  by  the  pressure  of  the  blood 
against  the  coats  of  the  arteries  at  each  contraction  cf  the 
ventricles. 

360.  The  following  experiment  will  demonstrate  that  the 
blood  flows  from  the  heart.     Apply  the  fingers  upon  the  artery 

358.  "What  is  the  course  of  the  veins  ?  What  peculiarity  is  observable 
in  the  veins  of  the  liver  ?  359.  How  often  does  the  heart  contract,  or  the 
pulse  beat,  in  adults  ?  In  infants  ?  In  old  persons  ?  What  is  said  of  the 
energy  of  its  contraction  in  different  persons  ?  How  is  the  pulse  produced  ? 
360.  Demonstrate  by  experiment  that  the  blood  flows  from  the  heart. 


Lo8  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

at  the  wrist,  at  two  different  points,  about  two  inches  apart  ; 
if  the  pressure  be  moderately  made,  the  "  pulse  "  will  be  felt 
at  both  points.  Let  the  point  nearest  the  heart  be  pressed 
firmly,  and  there  will  be  no  pulsation  at  the  lower  point ;  but 
make  strong  pressure  upon  the  lower  point  only,  and  the  pul- 
sation will  continue  at  the  upper  point,  proving  that  the  blood 
flows  from  the  heart,  in  the  arteries,  to  different  parts  of  the 
system. 

361.  There    are  several   influences,  either   separately   or 
combined  that  propel  the  blood  from  the  heart  through  the 
arteries,  among  which  may  be  named,  —  1st.  The  contraction 
of  the  muscular  walls  of  the  heart.     2d.'  The  contractile  and 
elastic  middle  coat  of  the  arteries  aids  the  heart  in  impelling 
the   blood    to   the    minute    vessels   of  the  system.     3d.  The 
peculiar  action  of  the  minute  capillary  vessels  is  considered, 
by  some  physiologists,  as  a  motive  power  in  the  arterial  circu- 
lation.    4th.  The  pressure  of  the  muscles  upon  the  arteries, 
when  in  a  state  of  contraction,  is  a  powerful  agent,  particu- 
larly when  they  are  in  active  exercise. 

362.  The  following  experiments  will  demonstrate  that  the 
blood  from  every  part  of  the*  system  flows  to  the  heart  by  the 
agency  of  the  veins.     1st.  Press  firmly  on  one  of  the  veins 
upon  the  back  of  the  hand,  carrying  the  pressure  toward  the 
fingers  ;  for  a  moment,  the  vein  will   disappear.     On  remov- 
ing the  pressure  of  the  finger,  it  will  reappear,  from  the  blood 
rushing  in  from  below. 

2d.  If  a  tape  be  tied  around  the  arm  above  the  elbow,  the 
veins  below  will  become  larger  and  more  prominent,  and  also 
a  greater  number  will  be  brought  in  view,  while  the  veins 
above  the  tape  are  less  distended.  At  this  time,  apply  the  fin- 
ger at  the  wrist,  and  the  pulsation  of  the  arteries  still  continues, 
showing  that  the  blood  is  constantly  flowing  from  the  heart 

361.  State  the  influences  that  propel  the  blood  from  the  heart.  362.  De- 
monstra^  by  the  first  experiment  that  the  blood  flows  to  the  heart.  By  th« 
second  experiment 


PHYSIOLOGY    OF    THE    CIRCULATORY    ORGANS.  1»>JI 

Hi  rough  the  arteries,  into  the  veins;  and  the  increased  size  of 
the  veins  shows  that  the  pressure  of  the  tape  prevents  its 
flowing  back  to  the  heart. 

363.  The  influences  that  return  the  blood  to  the  heart  through 
the  veins,  are  not  so  easily  understood  as  those  that  act  on  the 
blood  in  the  arteries.     Some   physiologists   have  imputed  an 
active  propulsive  power  to  the  capillary  vessels  in  carrying 
the  blood   through  the   veins.     This  is  not  easily  explained, 
and  perhaps  it  is  as  difficult  to  understand.     An  influence 
upon  which  others  have   dwelt,  is  the  suction  power  of  the 
heart  in  active  dilatation,  acting  as  a  vis  afronte  (power  in 
front)  in  drawing  blood  to  it. 

364.  Another  influence  that  aids  the  venous  circulation  is 
attributed  to  the  propulsive  power  of  the   heart.     It  is   not 
easy  to  compreheiad  how*  this    power   of  the   heart  can  be 
extended  through  the  capillary  vessels  to  the    blood  in  the 
veins.     Again,  an  important  agency  has  been  found,  by  some 
physiologists,  in  the  inspiratory   movements,  which  are   sup- 
posed to  draw  the  blood  of  the  veins  into  the  chest,  in  order 
to  supply  the  vacuum  which  is  created  there  by  the  elevation 
of  the  ribs  and  the  descent  of  the  diaphragm. 

365.  One  of  the  most  powerful  causes  which  influence  the 
venous  circulation,  is  the  frequently-recurring  action  of  the 
muscles  upon  the  venous  trunks.     When   the    muscles  are 
contracted,  they  compress  that  portion  of  the  veins  which  lie 
beneath  the  swell,  and  thus  force  the  blood  from  one  valve  to 
the  other,  toward  the  heart.     When   they  are    relaxed,  the 
veins  refill,  and  are  compressed  by  the  recurring  action  of 
the  muscles. 

Observation.     The   physician,  in  opening  a  vein,  relies  on 
the   energetic   contractions   and    sudden    relaxations    of   the 

363.  What  is  said  of  the  influences  that  return  the  blood  to  the  heart  ? 
What  is  said  of  the  propulsive  power  of  the  capillaries  ?  Of  the  suction 
power  of  the  heart  ?  364.  Give  another  influence.  State  another  agency. 
365.  What  is  one  of  the  most  powerful  causes  which  influence 
circulation  ?  Give  practical  observation. 
15 


no 


AM  ATOMY,    PHY310LOU*, 
Fig.  75. 


Fig  75.  An  ideal  view  of  the  circulation  in  the  lungs  and  system.  Prom  the  rfgii2 
ventricle  of  the  heart,  (2,)  the  dark,  impure  blood  is  forced  into  the  pulmonary 
artery,  (3,)  and  its  branches  (4,  5)' carry  the  blood  to  the  left  and  right  lung.  In 
the  capillary  vessels  (6,  6)  of  the  lungs,  the  blood  becomes  pure,  or  of  a  red  color, 
and  is  returned  to  the  left  auricle  of  the  heart,  (9,)  by  the  veins,  (7,  8.)  From  the 
left  auricle  the  pure  blood  passes  into  the  left  ventricle,  (10.)  By  a  forcible  contrac- 
tion oi  the  left  ventricle  of  the  heart,  the  blood  is  thrown  into  the  aorta,  (11.)  Its 
branches  (12,  13,  13)  carry  the  pure  blood  to  every  organ  or  part  of  the  body.  The 
divisions  and  subdivisions  of  the  aorta  terminate  in  capillary  vessels,  represented  by 
14,  14.  In  these  hair-like  vessels  the  blood  becomes  dark  colored,  and  is  returned 
to  the  right  auricle  of  the  heart  (1)  by  the  vena  cava  descendens,  (15,)  and  vena 
cava  ascendens,  (16.)  The  tricuspid  valves  (17)  prevent  the  rtflow  of  the  blood  from 
the  right  ventricle  to  the  right  auricle.  The  semiluiiar  valves?  (T8)  prevent  the  blood 
passing  from  the  pulmonary  artery  to  the  right  ventride.  Tb*  mitral  valves  (i°1  pr» 
vent  the  reflow  of  blood  from  the  left  ventricle  to  the  left  auricle.  The  semi'unaT 
valves  (30)  prevent  the  reflow  of  blood  from  the  aorta  to  toe  left  ventricle. 


PHYSIOLOGY  OF  THE  CIRCULATORY  ORGANS.      J71 

muscles,  when  he  directs  the  patient  to  clasp  the  head  of  a 
cane,  or  the  arm  of  a  chair ;  these  alternate  motions  of  the 
muscles  cause  an  increased  flow  of  blood  to  the  veins  of  the 
ligated  arm. 

366.  The  muscles  exercise  an  agency  in  maintaining  the 
venous  circulation  at  a  point  above  what  the  heart  could  per- 
form. As  the  pulsations  are  diminished  by  rest,  so  they  are 
accelerated  by  exercise,  and  very  much  quickened  by  violent 
effort.  There  can  be  little  doubt  that  the  increased  rapid- 
ity of  the  return  of  blood  through  the  veins,  is,  of  itself,  a 
sufficient  cause  for  the  accelerated  movements  of  the  heart, 
during  active  exercise. 

Observation.  The  quantity  of  blood  in  different  individuals 
varies.  From  twenty-five  to  thirty-five  pounds  may  be  consid- 
ered an  average  estimate  in  a  healthy  adult  of  medium  size. 
The  time  in  which  the  blood  courses  through  the  body  and 
returns  to  the  heart,  is  different  in  different  individuals.  Many 
writers  on  physiology  unconditionally  limit  the  period  to  three 
minutes.  It  is  undeniable  that  the  size  and  health  of  a  per- 
son, the  condition  of  the  heart,  lungs,  and  brain,  the  quantity 
of'  the  circulating  fluid,  the  amount  and  character  of  the 
inspired  air,  and  the  amount  of  muscular  action,  exert  a  mod- 
ifying influence.  The  time  probably  varies  from  three  to 
eight  minutes. 

366.  What  causes  the  accelerated  movements  of  the  heart  during  active 
exercise  ? 

Note.  Let  the  pupil  review  the  anatomy  and  physiology  of  the  circula 
tory  orgaus  from  fig.  75,  or  from  anatomical  outline  plates,  No.  6  and  7. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


CHAPTER    XIX. 

HYGIENE    OF    THE    CIRCULATORY    ORGANS 

367.  IF  any   part  of  the  system  is  deprived  of  blood,  its 
vitality  will  cease  ;  but,  if  the  blood  is  lessened  in  quantity  to 
a  limited  extent,  only  the  vigor  and  health  of  the  part  will  be 
impaired.     The   following  conditions,  if  observed,  will   favor 
the  free  and  regular  supply  of  blood  to  all   portions  of  the 
system. 

368.  The  clothing  should  be  loosely  worn.      Compression 
of  any  kind  impedes  the  passage  of  blood  through  the  vessels 
of  the   compressed    portion.     Hence,  no   article    of  apparel 
should  be  worn  so  as  to  prevent  a  free  flow  of  blood  through 
every  organ  of  the  body. 

369.  The  blood  which  passes  to  and  from  the  brain,  flows 
through  the  vessels  of  the  neck,     if  the  dressing  of  this  part 
of  the  body  is  close,  the  circulation  will  be  impeded,  and  the 
functions  of  the  brain  will  be  impaired.     This  remark  is  par- 
ticularly important  to  scholars,  public  speakers,  and  individu- 
als predisposed  to  apoplexy,  and  other  diseases  of  the  brain. 

370.  As  many  of  the  large  veins  lie  immediately  beneath 
the  skin,  through  which  the  blood  is  returned  from  the  lower 
extremities,  if  the   ligatures  used  to   retain  the  hose,  or  any 
other    article  of   apparel,    in  prrper    position,  be   tight  and 
inelastic,  the  passage  of  blood  through  these  vessels  will  be 


367—386.  Give  the  hygiene  of  the  circulatory  orgam.  367.  What  effect 
will  be  produced  on  the  body  if  it  is  deprived  of  blood  ?  If  the  blood  is 
only  lessened  in  quantity  ?  368.  Why  should  the  clothing  be  worn  loose  r 
369.  What  is  said  of  dressing  the  neck  ?  To  what  persons  is  this  remark 
applicable?  370.  How  are  enlarged  veins  frequently  produced  ? 


HYGIENE    OF    THE    CIRCULATORY    ORGANS.  17.'} 

obstructed,  producing,  by  their  distention,  the  varicose,  or 
enlarged  veins.  Hence  elastic  bands  should  always  be  used 
for  these  purposes. 

37 1 .  An  equal  temperature  of  all  parts  of  the  system  pro- 
motes health.     A  chill  on  one  portion  of  the  body  diminishes 
the    size  of  its    circulating   vessels,   and    the    blood    which 
should  distend  and  stimulate  the  chilled   part,  will  accumulate 
in  other  organs.    The  deficiency  of  blood  in  the  chilled  portion 
induces  weakness,  while  the  superabundance  of  sanguineous 
fluid  may  cause  disease  in  another  part  of  the  system. 

372.  The  skin  should  be  kept  not  only  of  an  equal,  but  at  its 
natural  temperature.    If  the  skin  is  not  kept  warm  by  adequate 
clothing,  so  that  chills  shall  riot  produce  a  contraction  of  the 
blood-vessels  and  a  consequent  paleness,  the  blood  will  recede 
from  the  surface  of  the  body,  and  accumulate  in  the  internal 
organs.     Cleanliness  of  the  skin  is  likewise  necessary,  for  the 
reason,  that  this  condition  favors  the  free  action  of  the  cutane 
ous  vessels. 

Observation.  When  intending  to  ride  in  a  cold  day,  wash 
the  face,  hands,  and  feet,  in  cold  water,  and  rub  them  smartly 
with  a  coarse  towel.  This  is  far  better  to  keep  the  extrem- 
ities warm,  than  to  take  spirits  into  the  stomach. 

373.  Exercise  promotes  the  circulation  of  the  blood.     As 
the  action  of  the  muscles  is  one  of  the  important  agents  which 
propel  the  blood   through    the  arteries  and  veins,  daily  and 
regular  exercise  of  the  muscular  system  is  required  to  sustain 
a  vigorous  circulation  in  the  extremities  and  skin,  and  also  to 
maintain  a  healthy  condition  of  the  system.     The  best  stimu- 
lants to  improve  the  sluggish  circulation  of  an  indolent  patient, 
whose  skin  is   pale  anc    whose  extremities  are  cold,  are  the 

371.  Why  should  the  temperature  of  the  body  be  equal  ?  372.  Why 
should  the  skin  be  kept  at  its  natural,  as  well  as  at  an  equal  temperature  ? 
What  practical  observation  when  intending  to  ride  in  a  cold  day  ?  373.  Why 
does  exercise  promote  health  ?  What  are  good  stimulants  for  sluggish 
circulation  in  the  indolent  ? 

15  * 


]  7-1  ANATOMY,  PHYSTOIOGY,   AND  HYGIENE. 

union  of  vigorous  muscular  exercise  with  agreeable  mental 
action,  and  the  systematic  application  to  the  skin  of  cold 
water,  attended  with  friction. 

Illustration.  The  coach-driver  and  teamster  throw  their 
arms  around  their  bodies  to  warm  them  when  cold.  The 
muscles  that  are  called  into  action  in  swinging  the  arms,  force 
a  greater  quantity  of  blood  into  the  chilled  parts,  and  conse- 
quently, more  heat  is  produced. 

374.  When  a  number  of  muscles  are  called  into  energetic 
action,    a  greater   quantity  of  blood  will  be  propelled  to  the 
lungs  and  heart  in  a  given  time,  than  when  the  muscles  are 
in  a  state  of  comparative  inaction.     It  is  no  uncommon  occur- 
rence, that  before  there  is  a  proper  expansion  of  the  respira- 
tory organs  to  correspond  with  the  frequency  and   energy  of 
the  movements  of  the  muscles,  there  is  an  accumulation  of 
blood  in  the  lungs,  attended  by  a  painful  sensation  of  fulness 
and  oppression  in  the  chest,  with  violent  and  irregular  action 
of  the  heart.     This  condition  of  the  organs  of  the  chest,  called 
congestion,  may  be  followed  by  cough,   inflammation  of  the 
'ungs,  asthma,  and  a  structural  disease  of  the  heart. 

375.  To  avoid  these  sensations  and   results,  when  we  feel 
necessitated  to  walk  or  run  a  considerable  distance  in  a  short 
time,  commence    the    movements    in    a    moderate   mannei 
increasing  the  speed  as  the  respiratory  movements  become 
more  frequent  and  their  expansion  more  extensive,  so  that  a 
sufficient  amount  of  air  may  be  received  into  the   lungs  to 
purify  the  increased  quantity  of  blood  forced  into  them.     The 
same  principles  should  be  observed  when  commencing  labor, 
and  in  driving  horses  and  other  animals. 

Observation.  When  a  large  number  of  muscles  are  called 
into  action  after  repose,  as  when  we  rise  from  a  recumbent  or 

Mention  the  illustration.  374.  What  is  the  effect  when  a  number  of 
muscles  are  called  into  energetic  action  ?  What  effect  has  this  accumu- 
lation of  blood  in  the  lungs  ?  37o.  How  can  such  disagreeably  sensations 
be  avoided  ?  Mention  a  practical  observation. 


HYGIENE    OF    THE    CIRCULATORY    ORGANS.  H5 

sitting  posture,  the  blood  is  impelled  to  the  heart  with  a  very 
strong  impetus.  If  that  organ  should  be  diseased,  it  may 
arrive  there  in  larger  quantities  than  can  be  disposed  of,  and 
death  may  be  the  result.  Hence  the  necessity  of  avoiding  ail 
sudden  and  violent  movements,  on  the  part  of  those  who  have 
either  a  functional  or  structural  disease  of  the  heart. 

376.  The  mind  exercises  no  inconsiderable  influence  upon 
the  circulatory  organs.     When  an  individual  is  stimulated  by 
hope,  or  excited  by  anger,  the  heart  beats  more  forcibly,  and 
the  arteries  act  more  energetically,  than  when  a  person  is 
influenced    by  fear,  despair,  or   sorrow.     Consequently,  the 
system  is  more  fully  nourished,  and  capable  of  greater  exer- 
tion, when  the  former  condition  obtains,  than  when  the  latter 
exists. 

377.  The  quality  and  quantity  of  the    blood   modify  the 
action    of   the    Jitart    and    Mood-vessels.      If    this   fluid    is 
abundant   and    pure,,  the    circulatory  vessels  act  with  more 
energy  than  when  it  is  deficient  in  quantity  or  defective  in 
quality. 

Illustrations.  1st.  In  an  athletic  man,  whose  heart  beats 
forcibly,  and  whose  pulse  is  strong,  if  a  considerable  quantity 
of  blood  is  drawn  from  a  vein,  as  in  bleeding,  the  heart  will 
beat  feebly,  and  the  pulse  will  become  weak. 

2d.  When  the  blood  is  made  impure  by  inhaling  vitiated  air, 
the  action  of  the  heart  and  arteries  is  diminished,  which  pro- 
duces an  effect  similar  to  that  which  takes  place  when  blood 
is  drawn  from  a  vein. 

378.  Hemorrhage  from  divided  arteries  should  be  imme 
diately  arrested.     When  large  blood-vessels  are  wounded  or 
cut,  the  flow  of  blood  must  be   immediately  stopped,  or  the 
person  soon  faints,  and  the  heart  ceases  its  action.     If  it  is  a 

376.  State  some  of  the  effects  that  the  mind  has  on  circulation. 
377.  What  effect  have  the  quantity  and  quality  of  blood  upon  the  circu- 
latory organs  ?  Give  illustration  1st.  Illustration  2d.  378.  What  is 
necessary  when  large  blood-vessels  are  wounded  or  cut  ? 


176 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


large  artery  that  is  wounded,  the  blood  will  be  thrown  out  in 
iets,  or  jerks,  every  time  the  pulse  beats.  The  flow  of  blood 
can  be  stopped  until  a  surgeon  arrives,  either  by  compressing 
the  vessel  between  the  wound  and  the  heart,  or  by  compress- 
ing the  end  of  the  divided  artery  in  the  wound. 


Fig.  76. 


Fig.  77. 


'rgF 

Fig.  76.  The  track  of  the  large  artery  of  the  arm.  1,  The  collar-bone.  9,  The 
axillary  artery.  10,  The  brachial  artery. 

Fig.  77.  B,  The  manner  of  compressing  the  artery  near  the  collar-bone.  A,  The 
manner  of  compressing  the  large  artery  of  the  arm,  with  the  fingers.  C,  The  manner 
of  compressing  the  divided  extremity  of  an  artery  in  the  wound,  with  a  finger. 

379.  After  making  compression  with  the  ringers,  as  de- 
scribed and  illustrated,  take  a  piece  of  cloth  or  handkerchief, 
twist  it  cornerwise,  and  tie  a  hard  knot  midway  between  the 

What  is  shown  by  fig.  76  ?  By  fig.  77  ?  379.  What  is  to  be  done  after 
compressing  the  wound,  as  before  described  ? 


HYGIENE    OF    THE    CIRCULATORY    ORGATSS.  17" 

iwo  ends.  This  knot  should  be  placed  over  the  artery,  be- 
tween the  wound  and  the  heart,  and  the  ends  carried  around 
the  limb  and  loosely  tied.  A  stick,  five  or  six  inches  long, 
should  be  placed  under  the  handkerchief,  which  should  be 
twisted  until  the  knot  has  made  sufficient  compression  on  the 
artery  to  allow  the  removal  of  the  fingers  without  a  return 
of  bleeding.  Continue  the  compression  until  a  surgeon  can 
be  called. 


Fig.  78. 


Fig.  79. 


Fig.  78.  A,  B,  The  track  of  the  large  artery  of  the  arm.  The  figure  exhibits  Uie 
method  of  applying  the  knotted  handkerchief  to  make  compression  on  this  artery. 

Fig.  79.  A,  C,  The  track  of  the  large  artery  of  the  thigh.  B,  The  method  of 
applying  the  knotted  handkerchief  to  compress  this  artery.  In  practice,  the  twisting 
stick  B  should  be  placed  opposite  the  knot  over  the  artery  A,  C. 

380.  When  an  artery  of  the  arm  is  cut,  elevating  the 
wounded  limb  above  the  head  will  tend  to  arrest  the  flow  of 
blood.  In  a  wound  of  a  lower  limb,  raise  the  foot,  so  that  it 
shall  be  higher  than  the  hip,  until  the  bleeding  ceases. 

Illustration.  On  one  occasion,  the  distinguished  Dr.  Na- 
than Smith  was  called  to  a  person  who  had  divided  one  of 

What  is  shown  by  fig.  78  and  79  ?  380.  What  suggestion  relative  to 
the  position  of  a  limb  when  bleeding  ?  Relate  a  simple  operation  by 
I)..  Nathan  Smith. 


178  ANATOM\,    PHYSIOLOGY,   AND    HYGIENE. 

the  large  arteries  below  the  knee.  After  trying  in  vain  to 
find  the  bleeding  vessel,  so  as  to  secure  it,  he  caused  the  foot 
to  be  elevated  higher  than  the  hip.  At  the  first  instant  the 
biood  was  forced  from  the  wound  about  twelve  inches ;  in 
a  minute,  it  was  diminished  to  three  or  four ;  and,  in  a 
short  time,  the  bleeding  ceased.  This  Dr.  S.  called  his 
"  great ""  operation ;  and  it  was  truly  great  in  simplicity 
and  science. 

381.  The  practical  utility  of  every  person   knowing   the 
proper  means  of  arresting  hemorrhage  from  severed  arteries, 
is  illustrated  by  the  following  incidents.     In  1848,  in  the  town 
of  N.,  Mass.,  a  mechanic  divided  the  femoral  artery;  although 
several  adult  persons  were  present,  he  died  in  a  few  minutes 
from  loss  of  blood,  because  those  persons  were  ignorant  of  the 
method  of  compressing  severed  arteries  until  a  surgeon  could 
be  obtained. 

382.  In  1846,  a  similar  accident  occurred  in  the  suburbs 
of  Philadelphia.     While  the  blood  was  flowing  copiously,  a 
lad,  who  had  received  instruction  on  the   treatment  of  such 
accidents  at  the   Philadelphia  High  School,  rushed   through 
the    crowd    that    surrounded    the    apparently    dying    man, 
placed  his   finger   upon  the    divided   vessel,   and    continued 
the  compression  until  the  bleeding  artery  was  secured  by  a 
surgeon. 

383.  In  "  flesh  wounds,"   when   no   large  blood-vessel  is 
divided,  wash  the  part  with   cold  water,  and,  when  bleeding 
has   ceased,   draw    the    incision  together,  and    retain  it  with 
narrow  strips  of  adhesive  plaster.     These   should  be  put  on 
smoothly,  and  a  sufficient  number  applied  to  cover  the  wound. 
In  most  instances  of  domestic  practice,  the  strips  of  adhesive 
plaster  are  too  wide.     They  should  not  exceed  in  width  one 

381.  Relate  the  first  incident  showing  the  utility  of  every  person  know- 
ing the  proper  method  of  arresting  the  flow  of  blood  from  divided  arte- 
ries. 382.  The  second  incident.  383  How  should  "  flesh  wounds  "  be 
dressed  ? 


HYGIENE    OF    THE    CIRCULATORY    ORGANS.  1"<9 

fourth  of  an  inch.  Then  apply  a  loose  bandage,  and  avoid 
all  "  healing  salves,"  ointments,  and  washes.  In  removing 
the  dressing  from  a  wound,  both  ends  of  the  strips  of  plaster 
should  be  raised  and  drawn  toward  the  incision.  The  lia- 
bility of  the  wound  re-opening  is  thus  diminished. 

Observation.  The  union  of  the  divided  parts  is  effected  by 
the  action  of  the  divided  blood-vessels,  and  not  by  salves  and 
ointments.  The  only  object  of  the  dressing  is  to  keep  the 
parts  together,  and  protect  the  wound  from  air  and  impurities. 
Nature,  in  all  cases  of  injuries,  performs  her  own  cure.  Such 
simple  wounds  do  not  generally  require  a  second  dressing 
and  should  not  be  opened  until  the  incisions  are  healed. 


Fig.  80. 


Fig.  80.    The  manner  in  which  strips  of  adhesive  planter  are  applied  to  wounds. 

384.  In  wounds  made  by  pointed  instruments,  as  a  nail,  or 
in  lacerated  wounds,  as  those  made  by  forcing  a  blunt  instru- 
ment, as  a  hook,  into  the  soft  parts,  there  will  be  no  direct 
and  immediate  union.     In  these  cases,  apply  a  soothing  poul- 
tice, as  one   made  of  linseed  meal,  and  also  keep  the  limb 
still.     It  is  judicious  to  consult  a  physician  immediately,  in 
punctured  or  lacerated  wounds,  because  they  often  induce 
the  most  dangerous  diseases. 

385.  Wounds  caused  by  the  bite  of  rabid  animals  or  ven- 
omous serpents,  should   be   immediately  cleansed   with  pure 

What  should  be  avoided  ?  How  should  the  strips  of  plaster  be  removed 
from  a  wound  ?  How  is  the  union  of  the  divided  parts  effected  ?  384.  How 
should  punctured  and  lacerated  wounds  be  dressed  ?  385.  What  is  the 
treatment  of  wounds  caused  by  the  bite  of  rabid  animals  ? 


i  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

water.  In  many  instances,  the  application  of  suction,  eithe, 
with  "  cupping  glasses,"  or  the  mouth,  will  prevent  the  intro- 
duction o£4l^f8^'o«otis*  matter  into  the  system  by  absorption. 
When  this  is  effected,  cover  the  wound  with  a  soothing 
poultice,  as  one  made  of  slippery  elm  bark. 

Observation.  Although  animal  poisons,  when  introduced 
.nto  the  circulating  fluid  through  the  broken  surface  of  the 
skin,  frequently  cause  death,  yet  they  can  be  taken  into  the 
mouth  and  stomach  with  impunity,  if  the  mucous  membrane 
which  lines  these  parts  is  not  broken. 

Fig.  81. 


Fig.  81.  a,  a,  Representation  of  wounds  on  the  back  part  of  the  arm  and  fore-arm 
6,  />,  Wounds  on  the  anterior  part  of  the  arm  and  fore-arm.  By  bending  the  elbow 
and  wrist,  the  incisions  at  a,  a,  are  opened,  while  those  at  i,  ft,  are  closed.  Were  the 
firm  extended  at  the  elbow  and  wrist,  the  wounds  at  a,  a,  would  be  closed,  and  those 
'at  6,  b,  would  be  opened. 

386.  The  proper  position  of  the  limbs  favors  the  union  of 
.vounds.  If  the  incision  be  upon  the  anterior  part  of  the  leg, 
between  the  knee  and  ankle,  extending  the  knee  and  bending 
the  ankle  will  aid  its  closing.  If  it  be  upon  the  back  part  of 
the  leg,  by  extending  the  foot  and  bending  the  knee,  thu 
gaping  of  the  incision  will  be  diminished.  When  wounds 
occur  upon  the  trunk  or  upper  extremities,  let  the  position  of 
the  person  be  regarded. 

386    Does  the  proper  position  of  the  limbs  favor  the  union  of  wounds  ? 


ANATOMY    OF    THE    LYMPHATIC    VESSELS. 


CHAPTER    XX. 

ABSORPTION. 

387.  ABSORPTION  is  the  process  by  which  the  materials  of 
nutrition  are  removed  from  the  alimentary  canal,  to  be  con- 
veyed into  the  circulatory  vessels.     It  *s  likewise  the  process 
by  which  the  particles  of  matter  that  have  become  injurious, 
or  useless,  are  removed  from  the  mass  of  fluids  and  solids 
of  which   the   body   is   composed.      These   renovating   and 
removing  processes  are  performed  by  two  sets  of  vessels 

ANATOMY  OF  THE  LYMPHATIC  VESSELS 

388.  The  vessels  that  act  exclusively  for  the  growth  and 
renovation  of  the   system,  are   found  only  in  the  alimentary 
canal.     They  are  called  lacteals.     The  vessels  whose  sole 
function  is  to  remove   particles  of  matter  already  deposited, 
are  called  Lym-phat'ics.     The  radicles,  or  commencement  of 
the  veins,  in  many,  and  it  may  be  in  all  parts  of  the  body, 
perform  the  office  of  absorption. 

Observation.  This  fact  accounts  for  the  capacity  of  the 
venous  system  exceeding  the  arterial.  Had  the  veins  no  other 
function  to  perform,  beside  returning  the  blood  that  had  been 
distributed  by  the  arteries,  it  would  be  reasonable  to  suppose 
that  this  system  would  be  less  than  the  arterial,  but  the  reverse 
is  known  to  be  true. 

389.  The   LYMPHATIC  VESSELS,  in  structure,  resemble  the 

387.  Define  absorption.  388  —  391.  Give  the  anatomy  of  the  lymphatic 
vensels.  388.  "What  are  those  vessels  called  that  act  exclusively  for  the 
growth  and  renovation  of  the  body  ?  Those  whose  office  is  to  remove  the 
atoms  already  deposited  ?  What  other  vessels  perform  the  office  of  ab 
•orption  ?  Give  observation.  389.  Describe  the  lymphatics 

16 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

iacteals.  They  exist  in  great  numbers  in  the  skin  and  mucous 
membranes,  particularly  those  of  the  lungs.  Though  no 
lymphatics  have  been  traced  to  the  brain,  it  is  presumed  that 
they  exist  there,  as  this  part  of  the  body  is  not  exempt  from 
the  composition  and  decomposition,  which  are  perpetual  in 
the  body.  These  vessels  are  extremely  minute  at  their  origin, 
so  that  in  many  parts  of  the  system  they  cannot  be  detected 
without  the  aid  of  a  microscope. 


Fig.  82.        Fig.  83.        Fig.  84. 


Big.  82.     A  single  lymphatic  vessel,  much  magnified. 

Fig.  83.    The  valves  of  a  lymphatic  trunk. 

Fig.  84.     1,  A  lymphatic  gland  with  several  vessels  passing  through  it. 

390.  The  lymphatic  vessels,  like  the  veins,  diminish  in 
number  as  they  increase  in  size,  while  pursuing  their  course 
toward  the  large  veins  near  the  heart,  into  which  they  pour 
their  contents.  The  walls  of  these  vessels  have  two  coats 
of  which  the  external  one  is  cellular,  and  is  capable  of  con- 
siderable distention.  The  internal  coat  is  folded  so  as  to  form 

What  is  represented  by  fig.  82  ?  By  fig.  83  ?  By  fig.  84  ?  390.  In  what 
respect  do  these  vessels  resemble  the  veins  of  the  system  ?  Give  the 
structure  of  their  coats. 


PITYSIOLOGV    OF    THE    LYMPHATIC    VESSELS.  IN3 

valves,  like  those   in   the  veins.     Their  walls  are  so  thin,  that 
these  folds  give  them  the  appearance  of  being  knotted. 

391.  At  certain  points,  the  lymphatic  vessels  pass  through 
distinct,  soft  bodies,  peculiar  to  themselves,  which  are  called 
lymphatic  glands,  which  are  to  these  vessels  what  the  mesen- 
teric  glands  are  to  the  lacteals.     The  lymphatic  glands  vary 
in  form  and  in   size.     They  are    extremely    vascular,   and 
appear  to  consist  of  a  collection  of  minute  vessels.     These 
glands  are  found  in  different  parts  of  the  body,  but  are  most 
numerous  in  the  groins,  axilla,  or  arm-pits,  neck,  and  cavities 
of  the  chest  and  abdomen. 

Observation.  From  exposure  to  cold,  these  glands  are 
frequently  enlarged  and  inflamed.  They  are  known  under 
the  name  of  "  kernels."  They  are  often  diseased,  particu- 
larly in  scrofula,  or  "  king's  evil." 

PHYSIOLOGY  OF  THE  LYMPHATIC  VESSELS. 

392.  Though  the  lacteals  and  lymphatics  resemble  each 
other  in  their  structure  and  termination,  yet  they  differ  as  to 
the  nature  of  the  fluids  which  they  convey,  as  well  as  the 
nature  of  their  functions.     The  lacteals  open  into  the  small 
intestine,  and  possess  the  power  of  rejecting  all  substances  in 
the  passing  aliment,  but  the  chyle.     The  lymphatics,  on  the 
contrary,  not  only  imbibe  all  the  various  constituents  of  the 
body,  both  fluid  and  solid,  but  they  sometimes  absorb  foreign 
and  extraneous  substances,  when  presented  to  their  mouths, 
as  in  vaccination. 

393.  The  varieties  of  absorption  are,   the    In-ter-stitial. 
Rec-re-men-ti'tial,  Ex-cre-men-ti'tial,  Cu-ta'ne-ous,  Res-pi'ra- 
to-ry,  Ve'nous,  and  the  Lac'te-al. 

391.  Describe  the  lymphatic  glands.  What  observation  is  given  in  regard 
to  these  glands  ?  392 — i03.  Give  the  physiology  of  the  lymphatic  ves 
sek.  392.  Explain  the  difference  between  the  lacteals  and  lymphatics 
393.  Name  the  varieties  of  absorption. 


184  ANATOMY.    PHYSIOLOGY,    AND    HYGIENE. 

394.  INTERSTITIAL  absorption  is  that  change  which  is  con 
stantly  going  on  in  the  animal  economy  among  the  panicles 
uf  matter  of  which  every  texture  is  composed.     The  ordinary 
functions  of  the  body,  in  health,  require  incessant  action  of  the 
lymphatics ;  the  circulatory  system,  with  its  myriads  of  small 
vessels,  is  constantly  depositing  new  atoms  of  matter,  which 
become  vitalized,  and  perform  a  course  of  actions,  then  die, 
or  become  useless.     These  old  atoms  are  removed   by   the 
absorbent  system.     Thus,  wherever  there  is  a  minute  artery 
to  deposit  a  living  particle  of  matter,  there  is  a  lymphatic 
vessel,  or  venous  radicle,  to  remove  it  as  soon  as  it  shall  have 
finished  its  particular  office. 

395.  The  action  of  the  lymphatic  vessels  counterbalances 
those  of  nutrition,  and  thus  the  form  and  size  of  every  part 
of  the  body  is  preserved.     When  their  action  exceeds  that  of 
the  nutrient  vessels,  the  body  emaciates  ;  when  it  is  deficient, 
plethora  is  the  result.     In  youth,  they  are  less  active  than  the 
nutrient  vessels,  and  the  limbs  are  plump ;  but  in  later  periods 
of  life,  we  find  these  actions  reversed,  and  the  body  diminishes 
in  size.     It  is  not  unfrequent  that  wens,  and  other  tumors  of 
considerable  size,  disappear,  and  even  the  entire  bone   of  a 
'imb  has  been  removed  from  the  same  general  cause.     The 
effused  fluids  of  bruises  are  also  removed  by  absorption. 

Observations.  1st.  When  little  or  no  food  is  taken  into  the 
stomach,  life  is  supported  by  the  lymphatic  vessels  and  veins 
imbibing  the  fat  and  reconveying  it  into  the  blood  vessels.  It  is 
the  removal  of  this  secretion  which  causes  the  emaciation  of 
the  face  and  extremities  of  a  person  recovering  from  a  fever. 
In  consumption,  the  extreme  attenuation  of  the  limbs  is  caused 
by  the  absorption,  not  only  of  the  fat,  but  also  of  the  muscles 
and  more  solid  parts  of  the  system. 

394.  What  is  interstitial  absorption?  How  are  the  new  atoms  of  mattei 
deposited  ?  How  removed  ?  395.  What  vessels  do  the  lymphatics  coun 
terbalance  in  action  ?  What  is  the  result  when  their  action  exceeds  tha 
of  the  nutrient  vessels?  When  it  is  less?  Mention  some  instances  ol 
active  absorption.  What  causes  the  emaciated  limbs  of  a  person  recovering 
from  fever  ?  The  extreme  attenuation  in  consumption  ? 


PHYSIOLOGY    OF    THE    LYMPHATIC    VESSELS.  185 

2d.  Animals  which  live  in  a  half  torpid  state  during  the 
winter,  derive  their  nourishment  from  the  same  source.  Ir 
other  words,  we  may  say  the  starving  animal  lives  for  a 
time  upon  itself,  eating  up,  by  internal  absorption,  such 
parts  of  the  body  as  can  be  spared  under  urgent  necessity, 
to  feed  those  organs  and  continue  those  functions  that  are 
absolutely  essential  to  life. 

396.  RECREMENTITIAL  absorption  is  the  removal  of  those 
fluids  from  the  system,  which  are  secreted  upon  surfaces  that 
have  no  external  outlet.     These  fluids  are  various,  as  the  fat, 
the  marrow,  the  synovia  of  joints,  serous  fluids,  and  the  humors 
of  the  eye.     Were  it  not  for  this  variety  of  absorption,  dropsy 
would  generally  exist  in  the  cavities  of  the  brain,  chest,  and 
abdomen,  from  the  continued  action  of  the  secretory  vessels. 

397.  EXCREMENTITIAL  absorption  relates  to  the  fluids  which 
have  been  excreted,  such  as  the  bile,  pancreatic  fluid,  saliva, 
milk,  and  other  secretions. 

398.  CUTANEOUS  absorption  relates  to  the  skin.     Here  the 
lymphatic  vessels  extend  only  to  the  cuticle,  which  they  do 
not  permeate.     There  has  been  much  diversity  of  opinion  on 
the  question  of  cutaneous  absorption ;  some  maintaining  that 
this  membrane  absorbs,  while  others  deny  it.     Many  experi- 
ments have  proved  that  the  skin  may  absorb  sufficient    nutri- 
ment to  support  life  for  a  time,  by  immersing  the  patient  in  n. 
bath  of  milk  or  broth.     It  has  been  found  that  the  hand,  im- 
mersed to  the  wrist  in  warm  water,  will  absorb  from  ninety 
to  one  hundred  grains  of  fluid  in  the  space  of  an  hour. 

399.  Thirst  may  be  quenched  by  applying  moist  clothes  to 
the  skin,  or  by  bathing.     It  is  no  uncommon  occurrence,  dur- 
ing a  passage  from  one  continent  to  the  other,  for  the  saliva 

396.  What  is  recrementitial  absorption?  397.  Define  excrementitial 
absorption.  398.  To  what  does  cutaneous  absorption  relate  ?  Is  there  a 
diversity  of  opinion  respecting  this  variety  of  absorption  ?  "What  do  well 
attested  experiments  show  ?  399.  What  remark  in  reference  to  quenching 
thirst  ?  What  agency  conveys  medicinal  substances  and  ointments  into 
the  system  when  Tabbed  on  the  skin? 

16* 


1S6  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

to  become  bitter  by  the  absorption  of  sea  water.  Medicinal 
substances,  such  as  mercuiy,  morphine,  and  Spanish  flies,  are 
frequently  introduced  into  the  system  through  the  skin. 

400.  RESPIRATORY  absorption  has  reference  to  the  lungs. 
The   mucous  membrane  of  these  organs  is  abundantly  sup- 
plied  with    lymphatic   vessels.     By  their   action,   substances 
finely  pulverized,  or  in  the  form  of  gas,  are  readily  imbibed 
when  inhaled  into  the  lungs,  such  as  metallic  vapors,  odorifer 
ous  particles,  tobacco  smoke,  and  other  effluvia.     In  this  way, 
contagious  diseases  are  frequently  contracted. 

Illustration.  In  inhaling  sulphuric  ether,  or  letheon,  it  is 
introduced  into  the  vessels  of  the  lungs  in  the  form  of  vapor, 
and  through  them  it  is  rapidly  conveyed  to  the  brain,  and  thus 
influences  the  nervous  system. 

401.  VENOUS  absorption  is  the  function  which  the  veins 
perform  in  absorbing  from  the  alimentary  canal  liquids  of 
various  kinds  that  have  been  taken  into  the  stomach  and  are 
not  converted  into  chyle.     In  other  parts  of  the  body,  they 
also  perform  the  common  office  of  lymphatics. 

402.  LACTEAL,  or  digestive  absorption  has  reference  to  the 
absorption  of  chyle  only,  which  is   destined  for  the  nutrition 
of  the  body. 

403.  Absorption  is  not  only  very  abundant,  but  generally 
very  rapid,  and  all  these  varieties  are  maintained  through  life, 
except  when  suspended  by  disease. 

400.  What  is  said  of  respiratory  absorption  ?  How  is  letheon  introduced 
into  the  system  ?  401.  Define  venous  absorption.  402.  What  is  lacteal 
absorption  ?  403.  What  is  said  of  absorption  ? 


Fig.  85.  A  representation  of  the  lymphatic  vessels  and  glands.  1,  2,  3,  4,  5,  6,  The 
lymphatic  vessels  and  glands  of  the  lower  limbs.  7,  Lymphatic  glands.  8,  The 
commencement  of  the  thoracic  duct.  9,  The  lymphatics  of  the  kidney.  10,  Of  the 
stomach.  11,  Of  the  liver.  12,  12,  Of  the  lungs.  13,  14,  15,  The  lymphatics  and 
glands  of  the  arm.  16,  17,  18,  Of  the  fuce  and  neck.  19,  20,  Large  veins  21,  The 
Jinracic  duct.  2(3,  The  lymphatics  of  the  heart. 


P1H  BIOLOGY    OF    THE    LYM1HAMC    VESSELS. 

Fig.  85. 


Io7 


i  - 


!P8  ANATOMY,    PHYSIOLOGY,    AND    HYGTENc.. 


HYGIENE   OF  THE   LYMPHATIC  VESSELS. 

404.  By  the   action   of  the  lymphatics,  substances   of  an 
injurious,  as  well  as  of  a  beneficial,  character  may  be  con- 
veyed  into  the  system.     These  vessels,  under  certain  condi- 
tions, are  more  active  in  their  office  than  at  other  periods  ; 
and  it  is  of  practical    utility  to  know  what  influences    their 
action. 

405.  The  function  of  these  vessels  is  increased  by  moisture, 
and  lessened  by  an  active  state  of  the  lacteals.     Observation 
shows  that  the  ill-fed,  and  those  persons  that  live  in  marshy 
districts,  contract  contagious  diseases  more  readily  than  those 
individuals  who  are  well  fed,  and  breathe  a  dry  and  pure  air. 

406.  The   air  of  the   sick-room  should    be  dry.      If  due 
attention  is  not  given  to  ventilation,  the  clothing  of  the  nurse 
and  patient,  together  with  the  air  of  the  room,  will  be  moist- 
ened  by   the   exhalations   from   the    skin   and    lungs.     This 
exhalation  may  contain  a  poison  of  greater  or  less  power, 
according    to  its    quantity  and  degree  of  concentration,  and 
may  be  absorbed  and  reconveyed  into  the    system,  causing 
inflammatory  diseases,  and  not  unfrequently  death. 

Observations.  1st.  When  we  are  attending  a  sick  person 
a  current  of  air  that  has  passed  over  the  patient  should  be 
avoided.  We  may  approach  with  safety  very  near  a  person  who 
has  an  infectious  disease,  provided  care  is  taken  to  keep  on  the 
side  from  which  the  currents  of  air  are  admitted  into  the  room. 

2d.  When  we  have  been  visiting  or  attending  on  a  sick 
person,  it  is  judicious  to  change  the  apparel  worn  in  the 
sick-room,  and  also  give  the  skin  a  thorough  bathing.  The 
outside  garments,  also,  should  be  aired,  as  poisonous  matter 
may  have  penetrated  the  meshes  of  the  clothing. 

4'H — 413.  Give  the  hygiene  of  the  lymphatic  vessels.  404.  "What  is  said 
respecting  the  action  of  the  lymphatic  vessels  ?  405.  What  influences  the 
function  of  these  vessels?  What  does  observation  show?  406.  Why 
should  the  air  of  the  sick-room  be  dry  ?  What  suggestion  when  we  ha\e 
breii  visiting  or  attending  on  the  sick? 


HYGIENE    OF    THE    LYMPHATIC    VESSELS.  189 

407.  The  stomach  should  be  supplied  with  food  of  a  nutrient 
and  digestible  character,  in  proper  quantities,  and  at  stated 
periods.     The  chyle  formed  from  the  food  stimulates  the  lac- 
teals  to  activity,  which  activity  is  attended  with  an  inactive 
state  of  the  lymphatics  of   the  skin   and  lungs.     Thus  due 
attention  should  be  given  to  the  food  of  the  attendants  on  the 
sick,  and  the  members  of  the  family.     Before  visiting  a  sick 
person  it  is  judicious  to  take  a  moderate  amount  of  nutritious 
food. 

Observation.  Many  individuals,  to  prevent  contracting  dis- 
ease that  may  be  communicated  from  one  person  to  another, 
use  tobacco,  either  chewed  or  smoked  ;  and  sometimes  alcohol, 
with  decoctions  of  bitter  herbs.  These  substances  do  not 
diminish,  but  tend  to  increase,  the  activity  of  the  lymphatics. 
Thus  they  make  use  of  the  means  by  which  the  poisonous 
matter  formed  in  the  system  of  the  diseased  person,  ma}  be 
more  readily  conveyed  into  their  own 

408.  The  skin  and  clothing,  as  well  as  the  bed-linen,  should 
be  frequently  cleansed.     This  will  remove  the  poisonous  matter 
that  may  be  deposited  upon  the  skin  and  garments,  which,  if 
suffered  to  remain,  might  be  conveyed  into  the  system   by 
the  action  of  the  lymphatics.     This  points  also  to  a  frequent 
change  of  the  wearing  apparel,  as  well  as  the  coverings  of 
the  bed.     In  visiting  the  unhealthy  districts  of  the  South  and 
West,  the  liability  of  contracting  disease  is  much  lessened  by 
taking  a  supply  of  food  at  proper  periods,  keeping  the  skin  and 
clothing  in  a  clean  state,  the  room  well  ventilated,  and  avoid- 
ing the  damp  chills  of  evening. 

409.  Absorption  by  the  skin  is  most  vigorous  when   the 
cuticle  is  removed  by  vesication,  or  blistering.     Then  exter- 

407.  Why  should  the  stomach  be  supplied  with  food  of  a  nutrient  and 
digestible  character  ?  What  is  said  of  the  use  of  alcohol,  or  tobacco,  in 
preventing  the  introduction  of  the  poisonous  matter  of  contagious  diseases  ? 
408.  Why  should  the  clothing  and  bed-linen  be  frequently  washed  ?  What 
suggestion  to  persons  in  visiting  the  unhealthy  districts  of  the  South  and 
Vv  cat  ?  409.  When  is  cutaueous  absorption  uiobt  \igorous>  ?  Why  ? 


190  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

nal  applications  are  brought  into  immediate  contact  with  the 
orifices  of  the  lymphatics  of  the  skin,  and  by  them  rapidly 
imbibed  and  circulated  through  the  system.  Thus  arsenic 
applied  to  the  cutaneous  vessels,  and  strong  solutions  of  opium 
to  extensive  burns,  have  been  absorbed  in  quantities  sufficient 
to  poison  the  patient. 

410.  WJien  the   cuticle    is   only  punctured    or   abraded, 
poisonous  matter  may  be  introduced  into  the  system.     The 
highly  respected  Dr.  W.,  of  Boston,  lost  his  life  by  poisonous 
matter  from  the  body  of  a  patient  subjected  to  a  post  mortem 
examination.     He  had   removed  from  his  finger,  previous  to 
the    examination,   a  "  hang-nail,"  and   the   poison  from  the 
dead  body  was  brought  in  contact  with  the  denuded  part,  and 
through  the  agency  of  the  lymphatics  it  was  conveyed  into  the 
system. 

411.  Puncture   any   part   of  the  cuticle   with   the   finest 
instrument  that  has  upon  its  point  the  smallest   conceivable 
quantity  of  the  vaccine  virus,  or  small-pox  matter,  and  it  will 
be   brought   into    contact    with   the   lymphatic   vessels,   and 
.hrough  their  agency  conveyed  into  the  system.     The  result 
is,  that  persons  thus  operated  upon  have  the  small-pox,    or 
the  vaccine  disease. 

412.  When  we  expose  ourselves  to  any  poisonous  vapors, 
or  handle  diseased  animals  or  sick  persons,  safety  and  health 
require  that  the  cuticle  be  not  broken  or  otherwise  injured.    In 
many  instances,  the   poisonous  animal  matter  upon  hides  has 
been  introduced  into  the  systems  of  tanners,  through  small 
ulcers  upon  their  fingers  or  hands.     From  these  sores  there 
would  be  seen  small  red  lines  extending  up  the  arm.     These 
swelled  tracts  indicate  an  inflammation  of  the  large  lymphatic 

410.  Do  the  same  results  follow,  if  the  cuticle  is  only  punctured  ?  Relate 
an  instance  of  death  by  the  absorption  of  poisonous  matter.  411.  By 
what  means  is  the  vaccine  matter  introduced  into  the  system  ? 
412.  What  caution  is  necessarj  when  we  expose  ourselves  to  poisonous 
rapors  ? 


HYGIENE    OF    THE    LYMPHATIC    VESSELS.  i 

trunks,  that  have  been  irritated  and  diseased  by  the  passage  of 
poisonous  matter  through  them  into  the  system. 

Observation.   A  distressing  illustration  of  the  absorption  of 
deleterious  substances  from  the   surface  of  a  sore,  is  seen  in 
the  favorite  experiments  of  that  class  of  "  quacks,"  who  style 
themselves  "  cancer  doctors."     With  them,  every  trifling  am* 
temporary  enlargement,  or  tumor,  is  a  cancer.     Their  gen 
eral  remedy  is  arsenic ;    and  happy  is   the  unfortunate  sul 
ferer  who  escapes  destruction  in  their  hands,  for  too  frequent 
ly  their  speedy  cure  is  death. 

413.  In  case  of  an  accidental  wound,  it  is  best  irnrne 
diately  to  bathe  the  part  thoroughly  in  pure  water,  and  to 
avoid  all  irritating  applications.  In  some  instances,  it  wouk< 
be  well  to  apply  lunar  caustic  immediately.  When  handling 
or  shrouding  dead  bodies,  or  removing  the  skin  from  animal* 
that  have  died  of  disease,  it  would  be  well  to  lubricate  the 
hands  with  olive-oil  or  lard.  This  affords  protection  to  the 
minute  portions  of  the  skin,  from  which  the  cuticle  may 
be  removed.  In  all  cases  where  there  is  an  ulcer  or  sore,  the 
part  should  be  covered  with  something  impervious  to  fluids, 
as  court-plaster,  before  exposing  the  system  to  any  animal, 
vegetable,  or  mineral  poison. 

413.  What  direction  is  given  when  the  cuticle  is  broken  ?     What  sug- 
"estion  is  given  when  shrouding  dead  bodies  ? 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


CHAPTER     XXI. 

SECRETION. 

414.  IN  the  human  body  are  found  many  fluids  and  solids 
of  dissimilar  appearance  and  character.     These  are  produced 
by  the  action  of  organs,  some  of  which  are  of  simple  struc- 
ture, while  others  are  very  complicated  in  their  arrangement 
These  organs  are  called  Se-cre'to-ry. 

ANATOMY  OF  THE  SECRETORY  ORGANS. 

415.  The  SECRETORY   ORGANS  are  the  Ex-ha'lants,  Folli- 
cles, and  the  Glands. 

416.  The  EXHALANTS  were  supposed  to  be  terminations  of 
arteries  or  capillaries.     The  external  exhalants  terminate  on 
the  skin  and  mucous  membranes  ;  the  internal  in  the  cellular 
and  medullary  tissues.     (Appendix  I.) 

Fig.  86. 


Fig.  86.  A  secretory  follicle.  An  artery  is  seen,  which  supplies  the  material  for  Itf 
secretion  Follicles  are  also  supplied  with  veins  and  organic  nerves. 

417.  The  FOLLICLES  are  small  bags,  or  sacs,  situated  in  the 
true  skin,  and  mucous  membrane.  The  pores  seen  on  the 
skin  are  the  outlets  of  these  bodies. 

414.  How  are  the  fluids  and  solids  of  the  body  produced  ?  415 — 419.  Girt 
the  anatomy  of  the  secretory  orrjaiis.  41-5.  Name  the  secretory  organs. 
416.  Describe  the  exhalants.  What  is  represented  by  fig.  86  ?  417-  Define 

follicles. 


PHYSIOLOGY    OF    THE    SECRETORY    ORGANS.  193 

418.  The  GLANDS  are  soft,  fleshy  organs,  and  as  various  in 
their  structure,  as  the  secretions  which  it  is  their  function  to 
produce.     Each  gland  is  composed  of  many  small  lobules 
united  in  a  compact  mass,  and  each  lobule  communicates  by 
a  small  duct  with  tne  principal  outlet,  or  duct  of  the  organ. 
Every  gland  is  supplied  with  arteries,  veins,  lymphatics,  and 
nerves.      These,  with  the  ducts,  are  arranged  in  a  peculiar 
manner,  and  connected  by  cellular  membrane. 

419.  There  are  two  classes  of  glands,  one  for  the  modi- 
fication of  the  fluids  which  pass  through  them,  as  the  mesenteric 
and  lymphatic  glands  ;  and  the  other  for  the  secretion  of  fluids 
which  are  either  useful  in  the  animal  economy,  or  require  to 
be  rejected  from  the  body. 


Fig.  87.    1, 1,  A  secretory  gland.    2,  2,  Minute  ducts  that  are  spread  through  tut 
glands.    These  coalesce  to  form  the  main  duct,  3. 


PHYSIOLOGY  OF  THE  SECRETORY  ORGANS. 

420.  SECRETION  is  one  of  the  most  obscure  and  mys 
tenous  functions  of  the  animal  economy.  "  It  is  that  process 
by  which  various  substances  are  separated  from  the  blood, 
either  with  or  without  experiencing  any  change  during  tlreir 

418.  Give  the  structure  of  the  glands.  419.  How  are  the  glands  arranged  ? 
420 — 431.  Give  the  pt.yswlogy  of  the  secretory  organs.  420.  What  is  secre 
tiou  ? 

I'l 


194  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

separation."  Not  only  is  the  process  by  which  substances  are 
separated  from  the  blood,  called  secretion,  but  the  same  term 
is  also  applied  to  substances  thus  separated.  Thus  physiolo- 
gists say,  that  by  the  process  of  secretion,  bile  is  formed  by 
the  liver ;  and  also,  that  bile  is  the  secretion  of  this  organ. 

421.  The  secreted  fluids  do  not  exist  in  that  form  in  the 
blood,  but  most  of  the  elements  of  which  they  are  made  do 
exist  in  this  fluid,  and  the  "  vessels  by  which  it  is  accomplished 
may  well  be  called  the  architects  and  chemists  of  the  system  ; 
for  out  of  the  same  material  —  the  blood  —  they  construct  a 
variety  of  wonderful  fabrics  and  chemical  compounds.     We 
see  the  same  wonderful  power  possessed,  also,  by  vegetables  ; 
for  out  of  the  same  materials  the   olive  prepares  its  oil,  the 
cocoa-nut  its  milk,  the  cane  its  sugar,  the  poppy  its  narcotic, 
the  oak   its  green  pulpy  leaves,  and  its  dense  woody  fibre. 
All  are  composed  of  the  same  few,  simple  elements,  arranged 
in  different  order  and  proportions." 

422.  "  In  like  manner  we  find   the  vessels,  in  animated 
bodies,  capable  of  forming  all  the  various  textures  and  sub- 
stances  which  compose  the  frame ;   the   cellular  tissue,  the 
membranes,  the  ligaments,  the  cartilages,  the  bones,  the  mar- 
row, the  muscles  with  their  tendons,  the  lubricating  fluid  of 
the  joints,  the  pulp  of  the  brain,  the  transparent  jelly  of  the 
eye ;  in  short,  all  the  textures  of  the  various  organs  of  which 
the  body  is  composed,  consist  of  similar  ultimate  elements, 
and  are  manufactured  from  the  blood." 

423.  Of  the   agents   that  produce   or  direct  the  different 
secretions,  we  have  no  very  accurate  knowledge.     Some  have 
supposed  this  function  to  be  mechanical,  others  a  chemical 
process,  but  experiments  prove  that  it  is  dependent  on  nervous 
influence.     If  the  nerves  are  divided  which  are  distributed  1o 


421.  "What  is  said  respecting  secreted  substances  ?  Do  vegetables  possess 
the  property  of  secretion  ?  422.  From  what  are  the  various  textures 
fonned  ?  423.  Have  we  accurate  knowledge  of  the  agents  that  produce 
secretion  s 


PHYSIOLOGY    OF    THE    SECRETORY    ORGANS.  195 

any  organ,  the  process  of  secretion  is  suspended.  It  is  no 
uncommon  occurrence,  that  the  nature  of  milk  will  be  so 
changed  from  the  influence  of  anger  in  the  mother,  as  to  cause 
vomiting,  colic,  and  even  convulsions,  in  the  infant  that  swal- 
lows it.  Unexpected  intelligence  either  of  a  pleasant  or 
unpleasant  character,  by  its  influence  on  the  nervous  system, 
will  frequently  destroy  the  appetite.  Sometimes  mental  agita- 
tion, as  fear,  will  cause  a  cold  sweat  to  pervade  the  surface* 
of  the  body. 

424.  Secretions  are  constantly  maintained,  during  life,  from 
the  serous  membrane,  by  the  action  of  the  internal  exhalants. 
The  fluid  which  is  exhaled  bears  some  resemblance  to  the 
serum  of  the  blood.     Its  use  is  to  furnish  the  organs,  which 
are  surrounded  by  this  membrane,  with  a  proper  degree  of 
moisture,  and  thus  enables  them  to  move  easily  on  each  other, 
as  those  within  the  chest  and  abdomen. 

425.  The  cellular  tissue  exhales  a  serous  fluid,  and  when 
it  becomes  excessive  in  quantity,  general  dropsy  is  produced. 
Fat  is  another  secretion,  which  is  thrown  out,  in  a  fluid  state, 
from  the  cellular  membrane.     It  is  deposited  in  little  cells, 
and  exists  in  the  greatest  abundance  between  the  skin  and  the 
muscles.     Its  use  seems  to  be,  to  form  a  cushion  around  the 
body  for  its  protection ;  to  furnish  nutriment  for  the  system 
when  food  cannot  be  taken  ;  to  supply  the  carbon  and  hydro- 
gen necessary  to  sustain  the  generation  of  heat,  when  these 
articles  of  combustion   are   not    otherwise    furnished.      The 
med'ul-la-ry  substance,  (marrow,)  in  the  cavities  of  the  long 
bones,  is  very  much  like  fat. 

Observation.  During  sickness,  if  there  is  not  emaciation 
or  absorption  of  this  secretion,  it  is  considered  an  unfavorable 
symptom,  because  it  indicates  a  want  of  power  in  the  absorb- 
ing system,  which  is  among  the  last  to  be  affected. 

How  is  it  proved  that  secretion  depends  on  nervous  influence  ?  424.  "What 
»s  said  of  the  secretions  from  the  serous  membrane  ?  425.  From  what  tissue 
is  a  serous  fluid  exhaled  ?  What  is  the  effect  when  this  fluid  becomes 
in  quantity  ?  What  is  fat :  Its  use  ?  What  is  marrow  ? 


li)6  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

426.  The  mucous  secretion  is  a  transparent,  viscid  fluid 
which  is  secreted  by  those  membranes  that  line  the  cavities 
of  tne  body,  which  have  an  external  communication,  as  the 
trachea  and  alimentary  canal.     This  secretion  serves  to  pro- 
tect these  parts  from  the  influence  of  the  air,  and  concurs,  by 
means  of  its  peculiar  properties,  in  the  performance  of  their 
functions. 

427.  There  are  two  external  secretions,  namely,  one  from 
the  skin,  called  perspiration,  and  the  other  from  the  lungs. 
The   cutaneous   exhalation,  or   transpiration*   exists  in   two 
forms,  called  sensible  perspiration  (sweat)  and  insensible  per- 
spiration.    The  pulmonary  exhalation  is  the  most  important 
and  universal,  and  closely  resembles  that  of  the  skin. 

428.  The  follicles  are  found  only  in  the  skin  and  mucous 
membrane.     They  secrete  an  oily,  unctuous  substance,  which 
mixes  with  the  transpiration,  and  lubricates  the  skin.     At  the 
root  of  each  hair  there  is  a  minute  follicle,  which  secretes  the 
fluid  that  oils  the  hair.     The  wax  in  the  passage  of  the  ear  is 
secreted  from  these  bodies. 

429.  All  the  blood  distributed   to  the  different  glands   is 
similar  in  composition  and  character  ;  but  the  fluids  secreted 
by  them,  vary  in  appearance  in  a  remarkable  degree.     The 
office  of  the  glands  appears  to  be  principally  to  form  different 
secretions.     Thus   the    salivary    glands     secrete   the    insipid 
saliva;  the  lachrymal  glands,  the  saline  tears;  the  liver,  the* 
yellow,  ropy  bile  ;  and  the  kidneys,  the  acrid  urine. 

430.  Some  secretions  are  evidently  produced  only  in  par- 


*  Transpiration  is  a  term  often  used  generically,  to  signify  the  pas- 
sage of  fluids  or  gases  through  membranes,  internally  or  externally  ; 
but  perspiration  is  a  specific  term,  signifying  transpiration  on  to  the 
external  surface. 

426.  What  is  said  relative  to  the  mucous  secretion  ?  427.  Name  the 
external  secretions.  428.  Give  the  office  of  the  follicles.  429.  What 
appears  to  be  the  principal  office  of  the  glands  ?  430.  Mention  a  secretion 
produced  in  a  particular  emergency. 


HYGIENE  OF  THE  SECRETORY  ORGANS.         19*7 

ticulur  emergencies,  as  is  seen  in  the  increased  secretion  of 
bony  matter  when  a  limb  is  broken. 

431.  When   any  substance    which    is   not   demanded    for 
nutrition,  or  does   not   give    nourishment   to   the    system,  is 
imbibed  by  the  lymphatic  vessels,  and  conveyed  into  the  blood, 
it  is  eliminated  in  the  secretions. 

Illustration.  A  few  years  since,  a  poor  inebriate  was 
carried  to  a  London  hospital  in  a  state  of  intoxication.  He 
lived  but  a  few  hours.  On  examining  his  brain,  nearly  half  a 
gill  of  fluid,  strongly  impregnated  with  gin,  was  found  in  the 
cavities  of  this  organ.  This  was  secreted  from  the  vessels  of 
the  brain. 

HYGIENE  OF  THE  SECRETORY  ORGANS. 

432.  Unless  the  secretions  are  regularly  maintained,  disease 
will  be  the  ultimate  result.     Let  the  secretions  from  the  skin 
be  suppressed,  and  fever  or  some  internal  inflammation  will 
follow.     If  the  bile  is  impeded,  digestion  will  be  impaired. 
If  any  other  secretion  is  suppressed,  it  will  cause  a  derange- 
ment of  the  various  internal  organs. 

Observation.  Ardent  spirits  derange  the  secretions,  and 
change  the  structure  of  the  brain.  This  is  one  reason  why 
inebriates  do  not  generally  live  to  advanced  age. 

433.  The  quantity  of  blood  influences  the  character  of  the 
secretions.     If  it  is  lessened  to  any  great  extent,  the  secre- 
tions will  be  lessened  as  well  as  changed  in  character. 

Illustration.  When  a  person  has  lost  a  considerable 
quantity  of  blood,  there  is  a  sensation  of  thirst  in  the  fauces, 
attended  with  a  cold,  pale,  dry  skin.  When  reaction  comes 

431.  What  becomes  of  those  substances  imbibed  by  the  lymphatics  that 
do  not  give  nourishment  to  the  body.  432 — 437.  Give  the  hygiene  of  the 
secretory  organs.  432.  What  effect  on  the  system  when  the  secretions 
are  not  regularly  maintained  ?  433.  Does  the  quantity  of  blood  influence 
the  secretions  ?  Give  an  illustration. 

17* 


198  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

on,  the  perspiration  is  cold,  attended  with  nausea,  and  some 
times  vomiting. 

434.  The  secretory  organs  require  the  stimulus   of  pu*~ 
blood.     If  this  fluid  is   vitiated,  the    action  of  the  secretor} 
organs  will  be  more  or  less  modified.     Either  the  quantity 
will  b3  affected  or  the  quality  will  be  altered. 

Observation.  The  impurity  of  the  blood  arising  from  the 
inhalation  of  the  vitiated  air  of  sleeping  rooms,  diminishes 
and  changes  the  character  of  the  secretions  of  the  mouth  and 
stomach.  This  accounts  for  the  thirst,  coated  tongue,  and 
disagreeable  taste  of  the  mouth  when  impure  air  is  breathed 
during  sleep.  The  disease  it  induces,  is  indigestion  or  dys- 
pepsia. 

435.  The  amount  of  action  modifies  the  condition  of  the 
secretory  organs.     When  a   secretory  organ    is  excessively 
stimulated,  its  vigor   and  energy  are  reduced.     The  subse- 
quent debility  may  be  so  great  as  to  suppress  or  destroy  its 
functional  power. 

Illustrations.  1st.  In  those  sections  of  the  country  where 
flax  is  spun  on  a  "  foot-wheel,"  it  is  not  unfrequent  that  the 
spinners  moisten  the  thread  with  the  secretions  of  the  mouth. 
This  seems  to  operate  economically  for  a  time,  but  debility  of 
the  salivary  organs  soon  follows,  which  incapacitates  them 
from  supplying  saliva  sufficient  to  moisten  the  food,  producing 
in  a  short  time  disease  of  the  digestive  organs. 

2d.  The  habit  of  continual  spitting,  which  attends  the 
chewing  of  tobacco  and  gums,  and  other  substances,  between 
meals,  induces  debility,  not  only  of  the  salivary  glands,  but 
of  the  system  generally. 

436.  One  secretory  organ  may  do  the  office  of  another. 
This  increased  action  of  a  secretory  organ  may  be  sustained 

434.  What  is  the  effect  of  impure  blood  on  the  secretory  organs  ? 
43o.  What  results  from  stimulating  excessively  a  secretory  organ  ?  How 
is  this  illustrated  ?  436.  What  is  the  effect  when  one  secretory  organ  per 
forms  the  office  of  another  ? 


HYGIENE  OF  THE  SECRETORY  ORGANS.         199 

for  a  limited  time  without  permanent  injury,  but,  if  long  con- 
tinued, a  diseased  action  of  the  organ  will  follow.  Of  mor- 
bid secretions  we  have  examples  in  the  ossification  of  the 
valves  of  the  heart,  cancerous  and  other  tumors. 

Observation.  In  the  evenings  of  the  warm  season,  a  chill 
upon  the  impressible  skin,  that  suppresses  the  perspiration,  is 
frequently  followed  by  a  diarrhoea,  dysentery,  or  cholera 
morbus.  These  can  be  prevented  by  avoiding  the  chill.  An 
efficient  means  of  relief,  is  immediately  to  restore  the  skin  to 
its  proper  action. 

437.  The  secretions  are  much  influenced  by  the  mind.  How 
this  is  effected,  it  is  difficult  to  explain  ;  but  many  facts  corrob- 
orate it.  Every  one  has  felt  an  increased  action  of  the  tear- 
glands  from  distressing  feelings.  Cheerfulness  of  disposition 
and  serenity  of  the  passions  are  peculiarly  favorable  to  the 
proper  performance  of  the  secretory  function.  From  this  we 
may  learn  how  important  it  is  to  avoid  such  things  as  distract, 
agitate,  or  harass  us. 

Observation.  In  fevers  and  other  diseases,  when  the  skin, 
mouth,  and  throat  are  dry  from  a  suppression  of  the  secretions, 
let  the  mind  of  the  patient  be  changed  from  despondency  to 
hope,  and  the  skin  and  the  membrane  that  lines  the  mouth  and 
throat  will  exhibit  a  more  moist  condition,  together  with  a 
general  improvement  of  the  vital  organs  of  the  system. 
Consequently,  all  just  encouragement  of  the  restoration  to 
health  should  be  given  to  a  sick  person. 

Give  examples  of  morbid  secretions.  "What  is  one  cause  of  dysentpry 
and  cholera  morbus  ?  How  can  these  affections  be  relieved  ?  437.  Show 
the  influence  of  the  mind  on  the  secretions.  Mention  instances  of  its 
influence. 


200  ANATOMY.    PHYSIOLOGY,    AND    HYGIENE 


CHAPTER     XXII. 

NUTRITION. 

438.  NUTRITION  is   the   vital   act  by   which  the  different 
parts  of  the  body  renew  the   materials  of  which   they  are 
composed.      Digestion,  circulation,    absorption,    and    respi- 
ration, are  but   separate    links    in    the    elmin    of   nutrition, 
which  would  be  destroyed   by  the  absence  of  any  one  of 
them. 

439.  The  nutritive  process  is  also  a  kind  of  secretion,  by 
which  particles  of  matter  are  separated  from  the  blood  and 
conveyed  with   wonderful   accuracy  to  the  appropriate  tex- 
tures.    The  function  of  the  nutrient  vessels  antagonizes  those 
of  absorption :  while  one  system  is  constructing,  with  beautiful 
precision,  the  animal  frame,  the  other  is  diligently  employed 
in  pulling  down  this  complicated  structure. 

440.  This  ever-changing  state  of  the  body  is  shown  by 
giving  animals  colored  matter,  mixed  with  their  food,  which 

'  in  a  short  time  tinges  their  bones  with  the  same  color  as 
the  matter  introduced.  Let  it  be  withdrawn,  and  in  a  few 
days  the  bones  will  assume  their  former  color  —  evidently 
from  the  effects  of  absorption.  The  changeful  state  of  the 
body  is  further  shown  by  the  losses  to.  which  it  is  subjected  ; 
by  the  necessity  of  aliment ;  by  the  emaciation  which  follows 
abstinence  from  food. 


438 — 454.  What  remarks  respecting  nutrition  f  438.  What  is  nutrition  ? 
439.  What  is  said  of  the  nutritive  process  ?  The  function  of  the  nutrient 
vessels  ?  440.  Give  a  proof  of  the  ever-changing  state  of  the  body.  Givf 
)ther  instarces  illustrative  of  the  changeful  state  of  the  body. 


NUTRITION.  201 

441.  Every  part  of  the  body  is  subject  to  this  continual 
change   of  material,  yet   it  is  effected  with  such   regularity, 
that  the  size,  shape,  and  appearance,  of  every  organ  is  pre- 
served ;  and  after  an  interval  of  a  few  years,  there  may  not 
remain  a  particle  of  matter  which  existed  in  the  system  at  a 
former  period.     Notwithstanding  this  entire  change,  the  per- 
sonal identity  is  never  lost. 

442.  Many  calculations  have  been  made  to  determine  ii> 
what  length  of  time  the  whole  body  is  renewed.     Some  have 
supposed  that  it  is  accomplished  in  four  years ;  others  have 
fixed  the  period  at  seven  years ;  but  the  time  of  the  change  is 
not  definite,  as  was  supposed  by  a  genuine  son  of  the  Emerald 
Isle,  who  had  been  in  America  seven  years  and  three  months, 
and  consequently  maintained  that  he  was  a  native  American. 

Observation.  India  ink,  when  introduced  into  the  skin,  is 
not  removed ;  hence  some  assert  that  this  tissue  is  an  excep- 
tion to  the  alternate  deposition  and  removal  of  its  atoms. 
The  ink  remains  because  its  particles  are  too  large  to  be 
absorbed,  and  when  in  the  skin  it  is  insoluble. 

443.  "  Those  animals  which  are  most  complicated  in  their 
structure,  and  are   distinguished  by  the  greatest  variety  of 
vital  manifestations,  are  subject  to  the  most  rapid  changes  of 
matter.      Such    animals    require    more    frequent   and    more 
abundant  supplies  of  food  ;  and,  in  proportion  as  they  are 
exposed  to  the  greater  number  of  external  impressions,  will 
be  the  rapidity  of  this  change  of  matter." 

444.  "  Animals  may  be  situated  so  that  they  lose  nothing 
by  secretion ;  consequently,  they  will  require  no  nutriment. 
Frogs  have  been  taken  from  fissures  in  solid  lime  rock,  which 

441.  Why  is  the  personal  identity  never  lost  in  the  change  of  materials, 
which  is  unceasing  in  the  system  ?  442.  Give  the  opinion  of  physiologists 
respecting  the  time  required  for  the  renewal  of  the  whole  body.  What 
exception  to  the  changing  state  of  the  different  textures  ?  443.  What 
animals  are  subject  to  the  most  rapid  changes  of  material?  444.  May 
animals  be  situated  so  that  they  require  no  nutriment  ?  What  is  related 
of  frogs  ? 


202  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

were  imbedded  many  feet  below  the  surface  of  the  earth,  and; 
on  being  exposed  to  the  air,  exhibited  signs  of  life." 

445.  The  renovation  of  the   bone,  muscle,  ligament,  ten- 
don, cartilage,  fat,  nerve,  hair,  &c.,  is  not  perfected  merely 
by  the  general  circulation  of  the  fluid  which  is  expelled  from 
the  left  side  of  the  heart,  but  through  the  agency  of  a  system 
of  minute  vessels,  which,  under  ordinary  circumstances,  can- 
not be  seen  by  the  eye,  even  when  aided  by  the  microscope  ; 
still,  minute  as  they  are,  the  function  of  these  agents  is  neces- 
sary to  the  continuance  of  life.     They  are  the  smallest  capil- 
lary vessels. 

446.  "  As  the  blood  goes  the  round  of  the  circulation,  the 
nutrient  capillary  vessels  select  and  secrete  those  parts  which 
are  similar  to  the  nature  of  the  structure,  and  the  other  por- 
tions pass  on ;  so  that  every  tissue  imbibes  and  converts  to  its 
own  use  the  very  principles  which  it  requires  for  its  growth ; 
or,  in  other  words,  as  the  vital  current  approaches  each  organ, 
the  particles  appropriate  to  it  feel  its  attractive  force,  —  obey 
it,  —  quit  the   stream,  —  mingle    with   the   substance    of  its 
tissue,  —  and   are   changed    into    its   own   true   and    proper 
nature." 

447.  Thus,  if  a  bone   is   broken,  a   muscle   or   a   nerve 
wounded,  and,  if"  the  system  is  in  a  proper  state  of  health, 
the  vital  economy  immediately  sets  about  healing  the  rupture. 
The  blood,  which  flows  from  the  wounded  vessels,  coagulates 
in  the  incision,  for  the  double  purpose  of  stanching  the  wound, 
and  of  forming  a  matrix  for  the  regeneration  of  the  parts. 
Very  soon,  minute  vessels  shoot  out  from  the  living  parts  into 
he  coagulum  of  the  blood,  and  immediately  commence  their 

operations,  and  deposit  bony  matter,  where  it  is  required 
to  unite  fractured  bones,  and  nervous  substance  to  heal  the 
wounded  nerve,  &c. 

44-5.  Show  how  the  renovation  of  the  bones,  muscles,  &c.,  is  perfected. 
440.  What  is  said  of  the  office  of  the  nutrient  capillary  vessels  ?  447-  When 
t  bone  is  irartured.  by  what  process  is  it  healed  ? 


NUTRITION 

448.  But  the  vital  economy  seems  not  to  possess  the  power 
of  reproducing  the   muscles   and   true  skin,  and    therefore; 
when  these  parts  are  wounded,  the  rupture  is  repaired  by  a 
gelatinous   substance,   which    gradually   becomes  hard,   and 
sometimes  assumes  something  of  a  fibrous  appearance.     It  so 
perfectly  unites  the  divided  muscle,  however,  as  to  restore  its 
functional  power.     When  the  cuticle  is  removed,  it  is  repro- 
duced and  no  scar  remains ;  but,  when  the  true  skin  is  de- 
stroyed, a  scar  is  formed. 

449.  It  is  not  uncommon  that  the  nutrient  arteries  have 
their  action  so  much  increased  in  some  parts,  as  to  produce 
preternatural  growth.     Sometimes  the  vessels  whose  function 
it  is  to   deposit  fat,  are  increased  in  action,  and  wens  of  no 
inferior  size  are  formed.     Again,  there  may  be  a  deposition 
of  substances  unlike  any  known  to  exist  in  the  body.     Occa- 
sionally, these  nutrient  arteries  of  a  part  take  on  a  new  action, 
and    not   only  deposit   their  ordinary  substance,  but  others, 
which  they  have  not  heretofore  secreted,  but  which  are  formed 
by  vessels  of  other  parts  of  the  body.     It  is  in  this  way  that 
we  account  for  the  bony  matter  deposited  in  the  valves  of  the 
heart  and  brain,  also  the  chalky  deposits  around  the  finger- 
joints. 

450.  In  infancy  and  childhood,  the  function  of  nutrition  is 
very  active  ;  a  large  amount  of  food   is  taken,  to  supply  the 
place  of  what  is  lost  by  the  action  of  the  absorbents,  and  also 
to  contribute  to  the  growth  of  the  body.     In  middle  age,  nutri- 
tion and  absorption  are  more  equal ;  but  in  old  age,  the  ab- 
sorbents are  more  active  than  the  nutrient  vessels.     The  size, 
consequently,  diminishes,  the  parts  become  weaker,  the  bones 
more    brittle,  the  body  bends   forward,  and    every  function 
exhibits  marks  of  decay  and  dissolution. 

451.  A  striking  instance  of  active  absorption  in  middle 

448.  What  occurs  when  a  muscle  is  divided  ?  449.  State  some  of  the 
results  of  an  increased  action  of  the  nutrient  arteries.  450.  When  is  nu- 
trition most  active  ?  How  in  middle  age  ?  How  in  old  age  ?  451.  Relate 
a  striking  instance  of  active  absorption  in  middle  age. 


'204  ANATOMY,    PHYSIOLOGY,    AND    HYGIENK. 

age  was  exhibited  in  the  person  of  Calvin  Edson,  of  Ver 
mont,  who  was  exhibited  in  the  large  towns  of  New  England, 
as  the  "  living  skeleton."  In  early  manhood  he  was  athletic, 
and  weighed  one  hundred  and  sixty  pounds  ;  but  the  exces- 
sive action  of  the  absorbents  over  the  nutrient  vessels,  re- 
duced his  weight,  in  the  interval  of  eighteen  years,  to  sixty 
pounds. 

452.  Instances,  on  the  other  hand,  have  occurred,  of  the 
action  of  the  nutrient  vessels  exceeding,  in  an  extreme  de- 
gree, those  of  absorption  ;  as  in  the  person  of  a  colored  girl, 
thirteen  years  of  age,  who  was  exhibited  in  New  York  in  the 
summer  of  1840.     She  was  of  the  height  of  misses  at  that 
age,  but  weighed  five  hundred  pounds.     Several  cases  are  on 
record  of  persons  weighing  eight  hundred  pounds. 

453.  As  already  mentioned,  the  blood  is  the  nutritive  fluid 
of  animals.     When  this  fluid  is  coagulated,  a  thick,  jelly-like 
mass  floats  in  the  serum,  called  coagulum.     This  coagulated 
mass    is    composed    of    fibrin    and    red    globulated    matter. 
The  color  of  the  red  globules  is  owing  to  the  presence  of 
iron,  though  some  physiologists  think  it  depends  on  an  animal 
substance  of  a  gelatinous  character. 

Observation.  That  portion  of  the  serum  which  remains 
fluid  after  coagulation  by  heat  has  taken  place,  is  called 
se-ros'i-ty.  It  is  more  abundant  in  the  blood  of  old,  than  in 
that  of  young  animals ;  and  it  forms  the  "  red  gravy  "  in 
roasted  meats. 

454.  The  blood  is  not  necessarily  red.:    It  may  be  white, 
ass  in  most  fish.     There  is  no  animal  in  which  the  blood  is 
equally  red  in  all  parts  of  the  body.     The  ligaments,  tendons, 
and  other  white  tissues   in  man  are  supplied   but  sparingly 
with   red  blood.     The    fluid    that   supplies   these   tissues   is 
whitish. 

452.  Of  excessive  nutrition  in  early  life.  453.  Describe  the  parts  that  enter 
into  the  composition  of  the  blood.  What  part  of  the  blood  forms  the  red  gravy 
in  roasted  meats  ?  454.  Is  the  blood  necessarily  red  ?  Of  what  color  is  the 
blood  of  the  fish  ''  What  part  of  the  human  system  has  white  blood  ? 


IIYttlRNF.    OF    NTnitlTTON.  205 


HYGIENE   OF  NUTRITION. 

455.  Healthy  nutrition  requires  pure  blood.     If  the  nutrient 
arteries  of  the  bones  are  supplied  with  impure  blood,  they 
will  become  soft  or  brittle,  their  vitality  will  be  impaired,  and 
disease  will  be  the  ultimate  result.     The  five  hundred  mus- 
cles receive  another  portion  of  the  blood.     These  organs  are 
attached  to,  and  act  upon  the  bones.     Upon  the  health  and 
contractile  energy  of  the  muscles  depends  the  ability  to  labor. 
Give   these    organs    of   motion   impure   blood,  which   is   an 
unhealthy  stimulus,  and  they  will  become  enfeebled,  the  step 
will    lose    its   elasticity,  the    movement   of  the  arm   will  be 
inefficient,  and  every  muscle  will  be  incapacitated  to  perform 
its  usual  amount  of  labor. 

456.  When   the    stomach,   liver,  and   other   organs   sub- 
servient to  the   digestion  of  food,  are  supplied  with  impure 
blood,  the  digestive  process  is  impaired,  causing  faintness  and 
loss  of  appetite,  also  a  deranged  state  of  the  intestines,  and, 
m  general,  all  the  symptoms  of  dyspepsia. 

457.  The  delicate   structure   of  the    lungs,  in   which   the 
blood  is  or  should  be  purified,  needs  the  requisite  amount  of 
pure  blood  to  give  them  vigor  and  health.     When  the  blood  is 
not  of  this  character,  the  lungs  themselves  lose  their  tone,  and, 
even  if  permitted  to  expand   freely,  have  not  power  fully  to 
change  the  impure  quality  of  this  circulating  fluid. 

458.  The  health  and   beauty  of  the  skin  require  that  the 
blood  should  be  well  purified ;  but,  if  the  arteries  of  the  skin 
receive  vitiated  blood,  pimples  and  blotches  appear,  and  the 
individual  suffers  from  "  humors."     Drinks,  made  of  various 


455 — 462.     Give  the  hygiene  of  nutrition.    455.  What  is  the  effect  of 
impure  blood  upon  the  bones  ?    On  the  muscles  ?    456.  On  the  digestive 
organs  ?    457.  On  the  lungs  ?    458.  What  is  the  effect  if  the  vessels  of  the 
skin  are  supplied  with  vitiated  blood  ? 
18 


206  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE 

kinds  of  herbs,  as  well  as  pills  and  powders,  are  taken  foi 
this  affection.  These  will  never  have  the  desired  effect, 
while  the  causes  of  impure  blood  exist. 

459.  If  the  nutrient  arteries  convey  impure  material  to  the 
brain,  the  nervous  and  bilious  headache,  confusion   of  ideas, 
loss   of  memory,  impaired    intellect,  dimness  of  vision,  and 
dulnass  of  hearing,  will  be  experienced  ;  and  in  process  of 
time,  the  brain  becomes  disorganized,  and  the  brittle  thread 
of  life  is  broken. 

Observations.  1st.  An  exertion  of  any  organ  beyond  its 
powers,  induces  weakness  that  will  disturb  the  nutrition  of  the 
part  that  is  called  into  action ;  and  it  recovers  its  energy 
more  slowly  in  proportion  to  the  excess  of  the  exertion.  The 
function  of  the  organ  may  be  totally  and  permanently  de- 
stroyed, if  the  exertion  is  extremely  violent.  We  sometimes 
see  palsy  produced  in  a  muscle  simply  by  the  effort  to  raise 
too  great  a  weight.  The  sight  is  impaired,  and  total  blind- 
ness may  be  produced,  by  exposure  to  light  too  strong  or  too 
constant.  The  mind  may  be  deranged,  or  idiocy  may  follow 
the  excess  of  study  or  the  over-tasking  of  the  brain. 

2d.  When  the  function  of  an  organ  is  permanently  impaired 
or  destroyed  by  over-exertion,  the  nutrition  of  the  part  is 
rendered  insufficient,  or  is  entirely  arrested  ;  and  then  the 
absorbents  remove  it  wholly  or  partially,  as  they  do  every 
thing  that  is  no  longer  useful.  Thus,  in  palsied  patients,  a 
few  years  after  the  attack,  we  often  find  scarce  any  trace  of 
the  palsied  muscles  remaining ;  they  are  reduced  almost  to 
simple  cellular  tissue.  The  condition  of  the  calf  of  the  leg, 
in  a  person  having  a  club-foot,  is  a  familiar  proof  of  this. 

460.  The  blood  may  be  made  impure,  by  the  chyle  being 
deficient  in  quantity  or  defective  in  quality.     This  state  of 


459.  How  does  impure  blood  affect  the  brain  ?  What  is  the  effect  when 
d.ny  organ  is  exerted  beyond  its  powers  ?  What  is  the  effect  when  an 
imian  is  permanently  impaired  ?  460.  How  may  the  blood  become  irnjmre  i 


HYGIENE    OF    NUTRITION.  '207 

the  chyle  may  be  produced  by  the  food  being  improper  in 
quantity  or  quality,  or  by  its  being  taken  in  an  improper 
manner,  at  an  improper  time,  and  when  the  system  is  not 
prepared  for  it.  The  remedy  for  impure  blood  produced  in 
any  of  these  ways  is  to  correct  the  injudicious  method  of 
using  food.  (See  Chapters  XV.  and  XVI.) 

461.  The  blood  may  also  be  rendered  impure,  by  not  sup- 
plying it  with  oxygen  in  the  lungs,  and  by  the  carbon  rot 
being  eliminated  from  the  system  through  this  channel.     The 
remedy  for  "  impurities  of  the  blood,"  produced  in  this  man- 
ner, would  be,  to  carefully  reduce  to  practice  the  directions  in 
the  chapters  on  the  hygiene  of  the   respiratory  organs,  rela- 
tive to  the  free  movements  of  the  ribs  and  diaphragm,  and 
the  proper  ventilation  of  rooms. 

462.  A  retention  of  the  waste  products  of  the  skin  produces 
impure  blood.     When  the  vessels  of  the  skin,  by  which  t'.ie 
waste,  useless  material  is  eliminated  from  the  system,  have 
become  inactive  by  improper  and  inadequate  clothing,  or  by 
a  want  of  cleanliness,  the  dead,  injurious  atoms  of  matter 
are    retained    in    ?.he    circulatory   vessels.      The    only   suc- 
cessful method  of  purifying  the  blood   and  restoring  health 
when  this  condition  exists,  is  to  observe  the  directions  given 
relative    to   clothir>g   and  bathing.     (See    Chapters   XXXIII. 
and  XXXIV.) 

Observation.  If  the  blood  has  become  "  impure,"  or 
"  loaded  with  humors,"  (an  idea  generally  prevalent,)  it  is 
not  and  cannot  be  "'  purified  "  by  taking  patent  pills,  powders, 
drops,  &c.  But,  on  the  contrary,  by  observing  the  suggestions 
in  the  preceding  paragraphs,  the  blood  can  be  freed  of  its 
impurities,  and,  what  is  of  greater  importance,  such  "  injurious 
humors  "  will  be  prevented. 

461.  Mention  another  means  by  which  the  blood  may  be  made  impure. 
How  remedied  462.  What  is  the  effect  of  want  of  cleanliness  upon  the 
olood  ?  What  is  said  respecting  "  humors  "  in  the  blood  ? 


208 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 
Fig.  88. 


Fig.  88.  A  front  view  of  the  organs  within  the  chest  and  abdomen.  1,  1,  1,  I,  The 
muscles  of  the  chest.  2,  2,  2,  2,  The  ribs.  3,  3,  3,  The  upper,  middle,  and  lower 
lobes  of  the  right  lung.  4,  4,  The  lobes  of  the  left  lung.  5,  The  right  ventricle  of 
the  heart.  6,  The  left  ventricle.  7,  The  right  auricle  of  the  heart.  8,  The  left  auri- 
cle. 9,  The  pulmonary  artery.  10,  The  aorta.  11,  The  vena  cava  dcscendens 
12,  The  trachea.  13,  The  (Esophagus.  14,  14, 14,  14,  The  pleura.  15,  15,  15,  The 
diaphragm.  16,  16,  The  right  and  left  lobe  of  the  liver.  17,  The  gall-cyst.  18,  The 
stomach  26,  The  spleen.  19,  19,  The  duodenum.  20,  The  ascending  colon 
21,  The  transverse  colon.  25,  The  descending  colon.  22,  22,  22,  22,  The  small 
intestine.  23,  23,  The  abdominal  walls  turned  down.  24,  The  thoracic  duct,  openi-:? 
•.nto  the  left  subrlavian  vein,  (27.) 


ANATOMY    OF    THE    RESPIRATORY    ORGANS.  209 


CHAPTER     XXIII. 

THE   RESPIRATORY    ORGANS. 

463.  THE  nutrient  portion  of  the  food  is  poured  into  the 
left  subclavian  vein,  (24,  27,  fig.  88,)  at  the  lower  part  of  the 
neck,  and  is  carried  to  the  right  cavities  of  the  heart.     The 
fluid  in  these  cavities  consists  of  the  chyle  incorporated  with 
the  impure  blood.     Neither  of  these  two  elements  is  fitted  to 
promote  the  growth  or  repair  the  waste  of  the  body.     They 
must  be  subjected  to  a  process,  by  which  the  first  can  be 
converted  into  blood,  and  the  second   freed  of  its  carbonic 
acid   gas  and   water.     This   is   effected  by  the  Respiratory 
Organs. 

ANATOMY  OF  THE  RESPIRATORY  ORGAJSTS. 

464.  The  RESPIRATORY  ORGANS   are   the  Lungs,  (lights,) 
the  Tra'che-a,  (windpipe,)  the  Bronch'i-a,  (subdivisions  of  the 
trachea,)  and  the  Air-  Ves'i-cles,  (air-cells  at  the  extremities  of 
the  bronchia.)     The  Di'a-phragm,  (midriff,)  Ribs,  and  several 
Muscles,  also  aid  in  the  respiratory  process. 

465.  The  LUNGS  are  conical  organs,  one  on  each  side  of 
the  chest,  embracing  the  heart,  (fig.  88,)  and  separated  from 
each   other  by  a  membranous    partition.     The  color  of  the 
lungs  is  a  pinkish  gray,  mottled,  and  variously  marked  with 
black.     Each  lung  is  divided  into  lobes,  by  a  long  and  deep 

463.  What  fluids  are  conveyed  into  the  right  cavities  of  the  heart  ? 
What  is  necessary  before  they  can  be  adapted  to  the  wants  of  the  body  ? 
By  what  organs  are  these  changes  effected  ?  464 — 474.  Give  the  anatomy 
yf  the  respiratory  organs.  464.  Name  the  respiratory  organs.  What  organs 
also  aid  in  the  respiratory  process  ?  465.  Describe  the  lungs. 

18* 


<MO  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

fissure,  which  extends  from  the  posterior  surface  of  the  uppei 
part  of  the  organ,  downward  and  forward,  nearly  to  the 
anterior  angle  of  the  base.  In  the  right  lung,  the  upper  lobe 
is  subdivided  by  a  second  fissure.  This  lung  is  larger  and 
shorter  than  the  left.  It  has  three  lobes,  while  the  left  has 
only  two. 

Fig.  89. 


Fig.  89.  A  back  view  of  the  heart  and  lungs.  The  posterior  walls  of  the  chest  ar* 
removed.  1,  2,  3,  The  uppe-,  middle,  and  lower  lobes  of  the  right  lung.  8, 9, 10,  The 
two  lobes  of  the  left  lung.  6,  13,  The  diaphragm.  7, 7,  14,  14,  The  pleura  that  lines 
the  ribs.  4,  11,  The  pleura  that  lines  the  mediastine.  5,  19,  12,  The  portion  of  the 
pleura  that  covers  the  diaphragm.  15,  The  trachea,  ]6,  The  larynx.  19,  19,  The 
right  and  left  bronchia.  20,  The  heart.  29,  The  lower  part  of  the  spinal  column. 


Explain  fig.  89. 


ANATOMY    OF    THE    RESPIRATORY    ORGANS.  211 

466.  Each  lung  is  enclosed,  and  its  structure  maintained 
6y  a  serous  membrane,  called  the  pleu'ra,  which  invests  it  as 
far  as  the  root,  and  is  thence  reflected  upon  the  walls  of  the 
chest.  The  lungs,  however,  are  on  the  outside  of  the  pleura, 
in  the  same  way  as  the  head  is  on  the  outside  of  a  cap  doubled 
upon  itself.  The  reflected  pleurae  in  the  middle  of  the  thorax 
form  a  partition,  which  divides  the  chest  into  two  cavities. 
This  partition  is  called  the  me-di-as~ti'num. 

Fig.  90. 


Fi?  30.  The  heart  and  lungs  removed  from  the  chest,  and  the  lungs  freed  from 
all  other  attachments.  1,  The  right  auricle  of  the  heart.  2,  The  superior  vena 
cava.  J,  The  inferior  vena  cava.  4,  The  right  ventricle.  5,  The  pulmonary  arterv 
Issuing  from  it.  a,  a,  The  pulmonary  artery,  (right  and  left,)  entering  the  lungs, 
ft,  6,  Bronchia,  or  air-tubes,  entering  the  lungs,  v,  v,  Pulmonary  veins,  issuing  from 
the  lungs.  6,  The  left  auricle.  7,  The  left  ventricle.  8,  The  aorta.  9,  The  upper 
tone  of  the  left  lung.  10,  Its  lower  lobe.  11,  The  upper  lobe  of  the  right  lung 
12,  The  middle  lobe.  13,  The  lower  lobe. 

Observation.   When  this  membrane  that  covers  the  lungs, 


466.  By  what  are  the  lungs  enclosed  ?  What  is  the  relative  position  of 
t'iie  lungs  and  pleura?  What  is  said  of  the  reflected  pleurae?  Explaiy 
fig.  90  What  part  of  the  lungs  is  affected  in  pleurisy  ? 


212  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

and    also   lines  the  chest,   is  inflamed,  the   disease  is  called 
"  pleurisy." 

467.  The  lungs  are  composed  of  the  ramiiicauons  of  the 
bronchial  tubes,  which  terminate  in  the  bronchial  cells,  (air- 
cells,)  lymphatics,  and  the  divisions  of  the  pulmonary  artery 
and  veins.     All  of  these  are  connected    by  cellular   tissue, 
which  constitutes  the  pa-ren'chy-ma.     Each  lung  is  retained 
in  its   place  by  its  root,  which  is  formed  by  the   pulmonary 
arteries,  pulmonary  veins,  and  bronchial  tubes,  together  with 
the  bronchial  vessels  and  pulmonary  nerves. 

468.  The  TRACHEA  extends  from  the  larynx,  of  which  it  is  a 
continuation,  to  the  third  dorsal  vertebra,  where  it  divides  into 
two  parts,  called  bronchia.     It  lies  anterior  to  the  spinal  col- 
umn, \from  which  it  is  separated  by  the  oesophagus. 

469.  The  BRONCHIA  proceed  from  the   bifurcation,   or  di- 
vision of  the  trachea,  to  their  corresponding  lungs.      Upon 
entering  the   lungs,  they  divide  into  two  branches,  and  each 
branch  divides  and  subdivides,  and  ultimately  terminates  in 
small  sacs,  or  cells,  of  various  sizes,  from  the  twentieth  to 
the  hundredth  of  an  inch  in  diameter.    So  numerous  are  these 
bronchial  or  air-cells,  that  the  aggregate  extent  of  their  lining 
membrane  in  man  has  been  computed  to  exceed  a  surface  of 
20,000  square  inches,  and  Munro  states  that  it  is  thirty  times 
the  surface  of  the  human  body. 

Illustration.  The  trachea  may  be  compared  to  the  trunk  of 
a  tree  ;  the  bronchia,  to  two  large  branches  ;  the  subdivisions 
of  the  bronchia,  to  the  branchlets  and  twigs  ;  the  air-cells,  to 
the  buds  seen  on  the  twigs  in  the  spring. 

470.  The  AIR- VESICLES  and  small  bronchial  tubes  compose 

467.  Of  what  are  the  lungs  composed  ?  How  retained  in  place  ? 
468.  Where  is  the  trachea  situated  ?  469.  Describe  the  bronchia.  What 
is  the  aggregate  extent  of  the  lining  membrane  of  the  air-cells  ?  To  what 
may  the  trachea  and  its  branches  be  compared  ?  470.  What  is  said  of 
the  air-cells  and  bronchial  tubes  ? 


ANATOMY    OF    THE    RESPIRATORY    ORGANS. 


213 


the  largest  portions  of  the  lungs.  These,  when  once  inflated, 
contain  air,  under  all  circumstances,  which  renders  their  spe- 
cific gravity  much  less  than  water;  hence  the  vulgar  term, 
lights,  for  these  organs.  The  trachea  and  bronchial  tubes 
are  lined  by  mucous  membrane.  The  structure  of  this  mem- 
brane is  such,  that  it  will  bear  the  presence  of  pure  air  without 
detriment,  but  no4,  of  other  substances. 

Fig.  91. 


F'g.  91.  A  representation  of  the  larynx,  trachea,  bronchia,  and  air-cells.  1,  1,  I 
<Yn  outline  of  the  right  lung.  2,  2,  2,  An  outline  of  the  left  lung.  3,  The  larynx 
4,  The  trachea.  5,  The  right  bronchial  tube.  6,  The  left  bronchial  tube.  7,  7,  7, 
6.  8,  8,  The  subdivisions  of  the  right  and  left  bronchial  tubes.  9,  9,  9,  9,  9  9,  Air 
tells. 

What  membrane  lines  the  trachea  and  its  branches  ?  What  is  peculiar 
in  its  structure  ?  What  does  fig.  91  represent  ? 


214  ANATOMY,    PHYSIOLOGY,  AND    HYGIENE. 

Observation.  The  structure  of  the  trachea  and  lungs  may 
be  illustrated,  by  taking  these  parts  of  a  calf  or  sheep  and 
nflating  the  air-vesicles  by  forcing  air  into  the  windpipe  with 
a  pipe  or  quill.  The  internal  structure  may  then  be  seen 
by  opening  the  different  parts. 

471.  The  lungs,  like  other  portions  of  the  system,  are  sup- 
plied with  nutrient  arteries  and  nerves.  The  nervous  filaments 
that  are  distributed  to  these  organs  are  in  part  from  the  tenth 
pair,  (par  vagum,)  that  originates  in  the  brain,  and  in  part  from 
the  sympathetic  nerve.  The  muscles  that  elevate  the  ribs  and 
the  diaphragm  receive  nervous  fibres  from  a  separate  system, 
which  is  called  the  respiratory. 

Fig.  92. 


Fig.  92.  1,  A  bronchial  tube.  2,  2,  2,  Air-vesicles.  Both  the  tube  and  vesiclec 
are  much  magnified.  3,  A  bronchial  tube  and  vesicles  laid  open. 

Observation.  When  the  mucous  membrane  of  a  few  of  the 
larger  branches  of  the  windpipe  is  slightly  inflamed,  it  is  called 
a  "  cold  ;"  when  the  inflammation  is  greater,  and  extends  to  the 
lesser  air- tubes,  it  is  called  bronch-itis.  When  the  air-cells 
and  parenchyma  become  inflamed,  it  is  called  inflammation 
of  the  lungs.  Coughing  is  a  violent  expulsory  effort  by  which 
air  is  suddenly  forced  through  the  bronchia  and  trachea  to 
remove  offending  matter. 

How  may  the  structure  of  the  trachea  and  its  branches  be  illustrated  ? 
471.  Are  the  lungs  supplied  with  nutrient  arteries  ?  "Where  are  the 
respiratory  nerves  distributed  ?  From  what  source  do  these  organs  derive 
their  nervous  filaments  ? 


ANATOMY    OF    THE    RESPIRATORY    ORGANS.  215 

472.  The  RIBS  are  joined  to  the  spinal  column  at  their 
posterior  extremity  ;  and  in  front,  they  terminate  in  cartilages, 
which  unite  them  to  the  sternum.  They  incline  downward, 
from  the  spinal  column  to  the  breast-bone,  and  form  resist- 
ing walls  that  assist  in  producing  the  partial  vacuum  necessr-arv 
for  inspiration. 

"Fig.  93.  Fig.  94. 


Pig  93.  A  section  of  the  chest  when  the  lungs  are  inflated.  1,  The  diaphragm. 
2,  The  muscular  walls  of  the  abdomen. 

Fig.  94.  A  section  of  the  chest  when  the  lungs  are  contracted.  1,  The  diaphragm 
in  common  expiration.  2,  2,  The  muscular  walls  of  the  abdomen.  3,  The  position 
of  the  diaphragm  in  forced  expiration. 

These  engravings  show  the  diaphragm  to  be  more  convex,  and  the  walls  of  the 
abdomen  more  flattened,  when  the  lungs  are  collapsed,  than  when  they  are  inflated 

473.  The  DIAPHRAGM  is  a  flexible  circular  partition,  *hat 
separates  the  respiratory  from  the  digestive  organs,  and  the 
chest  from  the  abdomen.  Its  margin  is  attached  to  the  spinal 
column,  the  sternum,  and  cartilages  of  the  lower  ribs.  The 
lungs  rest  upon  its  upper  surface,  while  the  liver  and  stomach 

472.  Describe  the  ribs.  Explain  figs.  93  and  94.  473.  Describe  the  ilia- 
phragiu. 


ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

are  placed  below  it,  (fig.  88.)  In  a  state  of  repose,  its  upper 
surface  forms  an  arch,  the  convexity  of  which  is  toward  the 
chest.  In  forced  expiration,  its  upper  point  reaches  as  high 
as  the  fourth  rib.  In  an  ordinary  inspiration,  it  is  depressed 
as  low  as  the  seventh  rib,  which  increases  the  capacity  of  the 
chest. 

474.  The  RESPIRATORY  muscles  are,  in  general,  attached 
at  one  extremity  to  the  parts  about  the  shoulders,  head,  and 
upper  portion  of  the  spinal  column.  From  these,  they  run 
downward  and  forward,  and  are  attached,  at  the  opposite 
extremity,  to  the  sternum,  clavicle,  and  upper  rib.  Other 
muscles  are  attached  at  one  extremity  to  a  rib  above,  and  by 
the  opposite  extremity  to  a  rib  below.  These  fill  the  spaces 
between  the  ribs,  and,  from  their  situation,  are  called  in-ter 
cost'al  muscles. 

Observation.  1st.  There  are  several  actions  of  common 
occurrence,  that  are  intimately  connected  with  respiration ; 
such  as  hiccough,  sneezing,  &c.  Hiccough  is  an  involuntary 
contraction  of  the  muscles  of  respiration,  particularly  the  dia- 
phragm. 

2d.  Sneezing  is  a  violent,  involuntary  contraction  of  the 
respiratory  muscles,  as  in  hiccough.  When  an  acrid  stimu- 
lant, as  snuff,  is  applied  to  the  mucous  membrane  of  the  nose, 
an  irritation  is  produced  which  is  accompanied  by  a  violent 
expulsion  of  air  from  the  lungs.  This  is  owing  to  the  con- 
nection between  the  nasal  and  respiratory  nerves. 

What  is  its  form  when  not  in  action  ?  474.  "Where  do  the  respiratory 
muscles  make  their  attachment  ?  What  name  is  given  to  those  muscles 
that  fill  the  places  between  the  ribs  ?  What  is  hiccough  ?  What  is 
sneezing  ? 


PHYSIOLOGY  OF  THE  RESPIRATORY  ORGANS. 


CHAPTER    XXIV. 

PHYSIOLOGY  OF  THE  RESPIRATORY   ORGANS. 

475  RESPIRATION,  or  breathing,  is  that  process  by  which  ail 
is  taken  into  the  lungs  and  expelled  from  them.  The  object  of 
respiration  is,  1st.  To  supply  the  system  with  oxygen,  which  is 
essential  to  the  generation  of  animal  heat ;  2d.  To  convert  the 
chyle  into  blood.  This  is  done  by  the  oxygen  of  the  inspired 
air ;  3d.  To  relieve  the  organs  of  the  body  of  the  principal 
elements  (carbon  and  hydrogen)  that  compose  the  old  and 
useless  particles  of  matter.  The  organs  of  the  system,  as 
already  mentioned,  are  principally  composed  of  carbon,  hy- 
drogen, oxygen,  and  nitrogen. 

476.  By  the  action  of  the  lymphatics  and  capillary  veins, 
the  old  and  worn-out  particles  are  conveyed  into  the  veins  of 
the  systemic  circulation.     The  hydrogen,  in  form  of  watery 
vapor,  is  easily  discharged  in  the  perspiration  and  other  secre- 
tions.    The  nitrogen  and  oxygen  are,  or  may  be,  separated 
from  the  blood,  through  the  agency  of  several  different  organs ; 
but  carbon  does  not  escape  so  readily.     It  is  probable  that  a 
part  of  the  surplus  carbon  of  the  venous  blood  is  secreted  by 
the  liver ;  but  a  far  greater  amount  passes  to  the  lungs,  and 
these  may  be  considered  as  special  organs  designed  to  sepa- 
rate this  element  from  the  venous  blood. 

477.  An  ordinary  inspiration  may  be  accomplished  by  the 
action  of  the  diaphragm,  and  a  slight  elevation  of  the  ribs.     In 


475 — 494.  Give  the  physiology  of  the  respiratory  organs.  475.  What  is 
respiration  ?  What  is  the  principal  object  in  breathing  5  476.  How  arc 
the  useless  atoms  of  matter  conveyed  in  >  the  veins  of  the  systemic  circu- 
lation ?  How  may  the  principal  elementary  suostances  be  separated  from 
the  blood  ?  477.  How  may  an  ordinary  inspiration  be  accomplished? 
19 


218 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


full  inspiration,  the  diaphragm  is  not  only  more  depressed 
hut  the  ribs  are  evidently  elevated.  To  produce  this  effect  on 
the  ribs,  two  sets  of  muscles  are  called  into  action.  Those 
which  are  attached  to  the  upper  rib,  sternum,  and  cavicle, 
contract  and  elevate  the  lower  and  free  extremities  of  the  ribs. 
This  enlarges  the  cavity  of  the  chest  between  the  spinal 
column  and  the  sternum.  But  the  lateral  diameter,  in  conse- 
quence, is  only  slightly  increased,  because  the  central  portion 
of  the  ribs  sinks  lower  than  their  posterior  extremities,  01 
their  cartilaginous  attachment  to  the  sternum. 


Fig.  95. 


3     2 


Fig.  95.  6,  Four  of  the  vertebra,  to  which  are  attached  three  ribs,  (7,  7,  7,)  with 
their  intercostal  muscles,  (8, 8.)  These  ribs,  in  their  natural  position,  have  their 
miterior  cartilaginous  extremity  at  4,  while  the  posterior  extremity  is  attached  to  the 
vertebrae,  (6,)  which  are  neither  elevated  nor  depressed  in  respiration.  1,  1,  and 
2,  y,  parallel  lines,  within  which  the  ribs  lie  in  their  natural  position.  If  the  anterior 
extremity  of  the  ribs  is  elevated  from  4  to  5,  they  will  not  lie  within  the  line  2,  2,  but 
will  reach  the  line  3,  3.  If  two  bands  extend  from  1,  1,  to  2,  2,  they  will  effectually 
prevent  the  elevation  of  the  ribs  from  4  to  5,  as  the  line  2,  2,  cannot  be  moved  to  3,  3. 

478.  The  central  portion  of  the  ribs  is  raised  by  the  actior 
of  intercostal  muscles.  The  first,  or  upper  rib,  has  but  'little 
movement ;  the  second  has  more  motion  than  the  first,  whilt 

What  effect  has  a  full  inspiration  on  the  ribs  and  diaphragm  ?  How  is 
the  chest  enlarged  between  the  spinal  column  and  sternum  ?  What  is  said 
of  the  lateral  diameter  of  the  chest  ?  Explain  fig.  95. 


PHYSIOLOGY  OF  THE  RESPIRATORY  ORGANS. 

the  third  has  still  more  than  the  second.  The  second  rib  is 
elevated  by  the  contraction  of  the  muscles  between  it  and  the 
first.  The  third  rib  is  raised  by  the  action  of  two  sets  of 
muscles  ;  one  lies  between  the  first  and  second  ribs,  the  other 
between  the  second  and  third.  The  motion  of  each  succeed- 
ing rib  is  increased,  because  it  is  not  only  acted  upon  by  the 
muscles  that  move  the  ribs  above,  but  by  an  additional  inter- 
costal ;  so  that  the  movement  of  the  twelfth  rib  is  very  free, 
as  it  is  elevated  by  the  contraction  of  eleven  muscles. 

479.  The  tenth  rib  is  raised  eight  times  as  much  as  the 
second  rib,  and  the  lateral  diameter  of  the  lower  portion  of  the 
chest  is  increased  in  a  corresponding  degree.     At  the  same 
time,  the  muscular  margin  of  the  diaphragm  contracts,  which 
depresses  its  central  portion ;  and  in  this  way,  the  chest  is 
enlarged    forward,  laterally,  and  downward,  simultaneously 
with  the  relaxation  of  the  walls  of  the  abdomen. 

480.  The  lungs   follow  the  variations  of  capacity  in  the 
chest,  expanding  their  air-cells  when  the  latter  is  enlarged, 
and  contracting  when  the  chest  is  diminished.     Thus,  when 
the  chest  is  expanded,  the  lungs  follow,  and  consequently  a 
vacuum  is  produced   in  their  air-cells.     The  air  then  rushes 
through  the  mouth  and  nose  into  the  trachea  and  its  branches, 
and  fills  the  vacuum  as  fast  as  it  is  made.     This  mechanical 
process  constitutes  inspiration. 

481.  After  the  expansion  of  the  chest,  the  muscles  that 
elevated  the  ribs  relax,  together  with  the  diaphragm.     The 
elasticity   of    the    cartilages    of   the    ribs    depresses    them, 
and  the  cavity  of  the  chest  is  diminished,  attended  by  the 
expulsion  of  a   portion  of  the  air  from  the  lungs.     At  the 
same   time,  the    muscles   that   form   the  front   walls  of  the 

478.    Describe   the  action  of   the  intercostal  muscles   upon  the   ribs. 

479.  How  does  the  elevation  of  the  tenth  rib  compare  with  the  second  ? 
What  effect  has  this  elevation  upon  the  lateral  diameter  of  the  chest  > 

480.  Describe  the  process  of  inspiration.     481.  Describe  the  process  by 
w  hich  the  air  is  forced  out  of  the  lungs. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

abdominal  cavity,  contract,  and  press  the  alimentary  canal, 
stomach,  and  liver,  upward  against  the  diaphragm;  this,  being 
relaxed,  yields  to  the  pressure,  rises  upward,  and  presses 
upon  the  lungs,  which  retreat  before  it,  and  another  portion 
of  air  is  expelled  from  these  organs.  This  process  is  called 
expiration. 

Fig.  96. 


Fig.  96.    A  front  view  of  the  chest  and  abdomen  In  respiration.    1,  1,  The  position 
f  the  walls  of  the  chest  in  inspiration.    2,  2,  2,  The  position  of  the  diaphragm  in 
nsprration.    3,  3,  The  position  of  the  walls  of  the  chest  in  expiration.    4,  4,  4,  The 
position  of  the  diaphragm  in  expiration.    5,  5,  The  position  of  the  walls  of  the  abdo- 
men in  inspiration.    6,  6,  The  position  of  the  abdominal  walls  in  expiration 

482.  Thus  it  is  obvious  that  the  enlargement  of  the  chest, 
or  inspiration,  is  produced  in  two  ways  :  1st.  By  the  depres- 
sion of  the  convex  portion  of  the  diaphragm  ;  2d.  By  the 
elevation  of  the  ribs.  On  the  contrary,  the  contraction  of  the 

Explain  fig.  96.  482.  In  how  many  ways  may  the  chest  be  enlarged,  and 
how  is,  it  accomplished  ?  How  is  the  contraction  of  the  chest  effected  ? 


PHYSIOLOGY    OF    THE    RESPIRATORY    ORGANS.  £X,\ 

chest,  or  expiration,  is  produced  by  the  depression  of  the  ribs, 
and  elevation  of  the  central  part  of  the  diaphragm.  These 
movements  are  successive  during  life,  and  constitute  res- 
piration. 

Fig.  97. 


Fig.  97.  A  side  view  of  the  chest  and  abdomen  in  respiration.  1,  The  cavity  of 
the  chest.  2,  The  cavity  of  the  abdomen.  3,  The  line  of  direction  for  the  diaphragm 
when  relaxed  in  expiration.  4,  The  line  of  direction  for  the  diaphragm  when  con- 
tracted in  inspiration.  5,  6,  The  position  of  the  front  walls  of  the  chest  and  «ndo- 
men  in  inspiration.  7,  8,  The  position  of  the  front  walls  of  the  abdomen  &nd  chest 
in  expiration. 

Experiment.  Place  the  ear  upon  the  chest  of  a  person, 
and  a  murmuring  sound  will  be  heard,  somewhat  like  the  soft 
sighings  of  the  wind  through  forest  trees.  This  sound  is 

Explain  fig.  97.     How  may  the  murmur  of  respiration  be  heard  ? 

19* 


ANATOMY,    PI1YS10LOUY,    AND    HYUIKNK. 

caused  by  the  air  rushing  in  and   out  of  the   lungs,  and   is 
peculiarly  distinct  in  the  child. 

483.  It  is   not  easy  to  decide  how  much  air  is  taken  into 
the  lungs  at  each  inspiration.     The  quantity,  however,  must 
vary  in  different  individuals,  from  the  difference  in  the  condi- 
tion and  expansion  of  the  lungs,  together  with  the  size  of  the 
chest.      From    numerous   experiments,   the    quantity,   at   an 
ordinary  inspiration,  of  a  common-sized  man,  is  fixed  at  forty 
cubic  inches.     It  has  been  estimated  that  one   hundred  and 
seventy  cubic  inches  can  be  thrown  out  of  the  lungs  by  a  for 
cible  expiration,  and  that  there  remain  in  the  lungs  two  hun- 
dred and  twenty  cubic  inches ;    so  that  these  organs,  in  their 
quiescent  state,  may  be  considered  as  containing  about  three 
hundred  and  ninety  cubic  inches  of  air,  or  more  than  a  gallon. 

484.  Respiration  is  more  frequent  in  females  and  children 
than   in  adult   men.     In  diseases,  particularly  those  of  the 
lungs,  it  is  more  increased  in  frequency  than  the  action  of  the 
heart.     In  health,  the  smallest  number  of  inspirations  in  a 
minute  by  an  adult,  is  not  less  than  fourteen,  and  they  rarely 
exceed  twenty-five.     Eighteen  may  be  considered  an  average 
number.     The  quantity  of  oxygen   taken  into  the   lungs  at 
each  inspiration  is  about  eight  cubic  inches,  one  half  of  which 
disappears  in  every  act  of  respiration. 

Observation.  Under  different  circumstances,  however,  the 
consumption  of  oxygen  varies.  It  is  greater  when  the  tern 
perature  is  low,  than  when  it  is  high ;  and  during  digestion 
the  consumption  has  been  found  one  half  greater  than  when 
the  stomach  was  empty. 

483.  Can  it  be  ascertained  with  accuracy  how  much  air  is  taken  into  the 
lungs  at  each  inspiration  ?  Why  not  ?  What  is  the  probable  quantity 
that  an  ordinary  sized  man  inspires  ?  How  much  can  be  thrown  out  of 
the  lungs  at  a  forcible  expiration,  and  how  much  remains  in  the  lungs  ' 
From  these  calculations,  how  much  may  they  contain  in  their  quiescent 
state?  484.  In  whom  is  respiration  most  frequent?  How  in  disease? 
How  in  health  ?  How  many  may  be  considered  an  average  number  ? 
When  is  the  consumption  of  oxygen  the  greatest  ? 


PHYSIOLOGY  OF  THE  RESPIRATORY  ORGANS,      223 

485.  Dr.  Southwood  Smith  has  lately  performed  a  series 
of  very  interesting  experiments,  from  which  he  deduces  the 
following  general  results:  "  1st.  The  volume  of  air  ordinarily 
present  in  the  lungs  is  ahout  twelve  pints.     2d.    The  volume 
of  air  received  by  the  lungs  at  an  ordinary  inspiration  is  ono 
pint.     3d.    The  volume  of  air  expelled  from  the  lungs  at  an 
ordinary  expiration,  is  a  little  less  than  one  pint.    4th.  Of  the 
volume  of  air  received  by  the  lungs  at  one  inspiration,  only 
one  fourth   part  is  decomposed  at  one  action  of  the  heart. 
5th.    The  quantity  of  blood  that  flows  to  the  lungs,  to  be  acted 
upon  by  the  air  at  one  action  of  the  heart,  is  two  ounces,  and 
this  is  acted  on  in  less  than  one  second  of  time.     6th.   The 
quantity  of  blood  in  the  whole  body  of  the  human  adult,  is 
twenty-five  pounds  avoirdupois,  or  twenty  pints.     7th.    In  the 
mutual  action  that  takes  place  between  the  air  and  blood, 
every  twenty-four   hours,  the    air  loses  thirty-seven   ounces 
cf  oxygen,  and  the  blood  fourteen  ounces  of  carbon." 

486.  Apparently,  atmospheric   air   is   a   simple   element. 
B  at  chemical  analysis  shows  its  composition  to  be  oxygen  and 
nitrogen,  in  the  proportion  of  twenty-one  parts  of  the  former, 
and  about  seventy-nine  of  the  latter.     In  addition,  there  is  a 
small   amount  of  vapor  of  water  and  cabonic  acid.     The  pres- 
sure of  this  invisible,  elastic  fluid  upon  the  body  of  an  ordinary 
sized  adult,  is  estimated  to  equal  thirty-five  thousand  pounds. 

487.  The  principal  substance  of  a  vitiated  character  in  the 
dark-colored  blood  is  carbonic  acid.     And  since  there  is  no 
chemical   affinity  between  the    oxygen  and  nitrogen   of  the 
air,  the  former  readily  unites  with  some  of  the  elements  of 
the    blood.      Hence,   whenever    blood    is   presented    to   the 

485.  State  the  1st,  2d,  3d,  and  4th  deductions  from  the  experiments  of  Dr. 
Southwood  Smith.  The  5th,  6th,  and  7th.  486.  Of  what  is  atmospheric  air 
composed  ?  What  is  the  weight  of  air  upon  a  common  sized  man  ?  487.  What 
is  the  principal  substance  of  a  vitiated  character  in  the  dark-colored  blood  1 
What  is  said  of  the  chemical  afP«ity  between  oxygen  and  nitrogen  ? 


'2^4  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

air  in  the  lungs,  the  oxygen  leaves  the  nitrogen,  and  becomes 
mixed  with  the  circulating  fluid.  (Appendix  J.) 

488.  Again,  carbonic  acid  and  water  have  a  stronger 
affinity  for  atmospheric  air  than  for  the  other  elements  of  the 
blood.  Consequently,  when  they  are  brought  into  contact 
with  the  air  in  the  lungs,  the  carbonic  acid  and  water  leave 
the  other  constituents  of  the  blood,  and  unite  with  the  air.  In 
this  way  the  bluish,  or  impure  blood  is  relieved  of  its  impu- 
rities, and  becomes  the  red,  or  pure  blood,  which  contains  the 
principles  so  essential  to  life.  (Appendix  K.) 

489-  The  formation  of  carbonic  acid  and  water,  eliminated 
from  the  system  through  the  lungs  and  skin,  is  explained  b} 
the  following  theory :  In  the  lungs  and  upon  the  skin  the 
oxygen  separates  from  the  nitrogen  and  unites  with  the  blood 
in  the  capillary  vessels  of  these  organs.  The  oxygen  is  con- 
veyed with  the  blood  to  the  capillary  arteries  and  veins  of  the 
different  tissues  of  the  system.  In  these  membranes  there  is 
a  chemical  union  of  the  oxygen  with  the  carbon  and  hydrogen 
contained  in  the  blood  and  waste  atoms  of  the  system.  This 
combustion,  or  union  of  oxygen  with  carbon  and  hydrogen,  is 
attended  with  the  disengagement  of  heat,  and  the  formation 
of  carbonic  acid  and  water.  .(Appendix  L.) 

490.  The  following  experiment  will  illustrate  the  passage 
of  fluids  through  membranes,  and  the  different  affinity  of 
gases  for  each  other.  Put  a  mixture  of  water  and  alcohol 
into  a  phial  and  leave  it  uncorked.  Both  the  water  and 
alcohol  have  a  greater  affinity  for  air  than  for  each  other. 
Alcohol  has  a  greater  affinity  for  the  air,  and  will  be  diffused 
through  it  more  readily  than  the  water,  when  there  is  no 
intervening  obstacle.  But  tie  a  piece  of  bladder  over  the 
mouth  of  the  phial,  and  let  it  stand  a  few  days,  —  the  watei 

488.  What  is  formed  when  oxygen  unites  with  carbon  or  hydrogen  ? 
489.  Give  the  theory  for  the  formation  of  carbonic  acid  and  watery  vapor 
thrown  out  of  the  system.  490.  Illustrate  the  passage  of  fluids  through 
membranes,  and  the  different  affinities  of  gases. 


PHYSIOLOGY    OF    THE    RESPIRATORY    ORGANS.  225 

will  leave  the  alcohol,  and  pass  through  the  membrane.  By 
the  aid  of  this  experiment,  we  shall  endeavor  to  explain  the 
interchange  of  fluids  in  the  lungs. 

491.  The  walls  of  the  air-vesicles,  and  coats  of  the  blood- 
vessels, are  similar,  in  their  mechanical  arrangement,  to  the 
membranous  bladder  in  the  before  described  experiment. 
As  the  oxygen  of  the  air  has  greater  affinity  for  blood  than  for 
nitrogen,  so  it  permeates  the  membranes  that  intervene  be- 
tween the  air  and  blood  more  readily  than  the  nitrogen. 
As  the  carbonic  acid  and  water  have  a  greater  affinity  for 
air  than  for  the  other  elements  of  the  blood,  so  they  will  also 
pass  through  the  walls  of  the  blood-vessels  and  air-cells  more 
readily  than  the  other  elements  of  the  dark-colored  blood. 


Fig.   98.     1,  A   bronchial  tube  divided  into  three  branches.     2,  2,  2,  Air-cells 

3,  Branches  of  the  pulmonary  artery,  that  spread  over  the  air-cells.    Through  the 
pulmonary  artery  the   dark,  impure   blood  is  carried  to  the  air-cells  of  the  lungs. 

4,  Branches  of  the  pulmonary  vein,  that  commence  at  the  minute  terminations  of  the 
pulmonary  artery.     Through  the  pulmonary  vein  the  red  blood  is  returned  to  the  heart. 

492.  As  the  impure  blood  is  passing  in  the  minute  vessels 
over  the  air-cells,  the  oxygen  passes  through  the  thin  coats  of 
the  air«cells  and  blood-vessels,  and  unites  with  the  blood.  At 
the  same  time,  the  carbonic  acid  and  water  leave  the  blood t 
and  pass  through  the  coats  of  the  blood-vessels  and  air-cells, 
and  mix  with  the  air  in  the  cells.  These  are  thrown  out  of  the 
system  every  time  we  breathe.  This  interchange  of  products 
produces  the  change  in  the  color  of  the  blood. 

Explain  fig.  98.     492.  How  and  where  is  the  blood  changed  ? 


226 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


Experiment.  Fill  a  bladder  with  dark  blood  drawn  iron; 
any  animal.  Tie  the  bladder  closely,  and  suspend  it  in  the 
air.  In  a  few  hours,  the  blood  next  the  membrane  will  have 
become  of  a  bright  red  color.  This  is  owing  to  the  oxygen 
from  the  air  passing  through  the  bladder,  and  uniting  with 
the  blood,  while  the  carbonic  acid  has  escaped  through  the 
membrane. 

Fig.  99. 


P'g.  99.  An  ideal  view  of  the  pulmonary  circulation.  1,  1,  The  right  lung. 
2,  2,  The  left  lung.  3,  The  trachea.  4,  The  right  bronchial  tube.  5,  The  left 
bronchial  tube.  6,  6,  6,  6,  Air-cells.  7,  The  right  auricle.  8,  The  right  ventricle. 
9  The  tricuspid  valves.  10,  The  pulmonary  artery.  11,  The  -branch  to  the  light 
lung.  12,  The  branch  to  the  left  lung.  13,  The  right  pulmonary  vein.  14,  The 
left  pulmonary  vein.  15,  The  left  auricle.  16,  The  left  ventricle.  17,  The 
mitral  valves. 

493.  The  presence  of  carbonic  acid  and  watery  vapor  in 
the  expired  air,  can  be  proved  by  the  following  experiments: 

Give  the  experiment  showing  that  oxygen  changes  the  dark-colored 
blood  to  a  bright  red  color.  What  is  represented  by  fig.  99  ?  493.  How  cat 
the  |j;-fsi'i;ce  of  carbonic  acid  in  the  lungs  be  proved  ? 


PHYSIOLOGY    OF    THE    RESPIRATORY    ORGANS.  221 

1st.  Breathe  into  lime-water,  and  in  a  few  minutes  it  will 
become  of  a  milk-white  color.  This  is  owing  to  the  carbonic 
acid  of  the  breath  uniting  with  the  lime,  forming  the  car- 
bonate of  lime.  2d.  Breathe  upon  a  cold,  dry  mirror  for  a 
few  minutes,  and  it  will  be  covered  with  moisture.  This  is 
condensed  vapor,  from  the  lungs.  In  warm  weather,  this 
watery  vapor  is  invisible  in  the  expired  air,  but  in  a  cold,  dry 
morning  in  winter,  the  successive  jets  of  vapor  issuing  from 
the  mouth  and  nose  are  sufficiently  obvious. 

494.  From  the  lungs  are  eliminated  other  impurities  be- 
side carbonic  acid,  the  perceptible  quality  of  which  is  vaiious 
in  different  persons.  The  offensive  breath  of  many  persons 
may  be  caused  by  decayed  teeth,  or  the  particles  of  food  that 
may  be  retained  between  them,  but  it  often  proceeds  from  the 
secretion,  in  the  lungs,  of  certain  substances  which  previously 
existed  in  the  system. 

Illustration.  When  spirituous  liquors  are  taken  into  the 
stomach,  they  are  absorbed  by  the  veins  and  mixed  with  the 
dark-colored  blood,  in  which  they  are  carried  to  the  lungs  to 
be  expelled  from  the  body.  This  will  explain  the  fact,  which 
is  familiar  to  most  persons,  that  the  odor  of  different  sub- 
stances is  perceptible  in  the  breath,  or  expired  air,  long  after 
the  mouth  is  free  from  these  substances. 

How  the  watery  vapor  ?  494.  Are  there  other  excretions  from  the  lungs  ? 
Give  the  illustration. 

Note.  Let  the  anatomy  and  physiology  of  the  respiratory  organs  b< 
reviewed  from  ngs,  96,  97,  and  99,  or  from  anatomical  outline  jlates  Noa. 
6  and  7 


'228  ANATOMY,    PHYSIOLOGY,    AND   HYGIENE. 

CHAPTER     XXY. 

HYGIENE    OF   THE    RESPIRATORY    ORGANS. 

495.  FOR  man  to  enjoy  the  highest  degree  of  health,  ii 
is  necessary  that  the  impure  "venous"  blood  be  properly 
changed.     As  this  is  effected  in  the  lungs  by  the  action  of  the 
air,  it  follows  that  this  element,  when  breathed,  should  be 
pure,  or   contain  twenty-one   per  cent,  of  oxygen  to  about 
seventy-nine  per  cent,  of  nitrogen. 

496.  The  volume  of  air  expelled  from  the  lungs  is  some- 
what less  than  that  which  is  inspired.     The  amount  of  loss 
varies  under  different  circumstances.     An  eightieth  part  of 
the  volume  taken  into  the  lungs,  or  half  a  cubic  inch,  may  be 
considered  an  average  estimate. 

497.  The  quality  and  purity  of  the  air  is  affected  by  every 
respiration.     1st.    The    quantity   of   oxygen   is   diminished. 
2d.  The  amount  of  carbonic  acid  is  increased.     3d.  A  certain 
proportion  of  watery  vapor  is  ejected  from  the  lungs  in  the 
expired   air.     Of   the    twenty-one    parts    of  oxygen   in   the 
inspired  air,  only  eighteen  parts  are  expired,  while  the  car- 
bonic acid  and  watery  vapor   are  increased   about  four  per 
cent.     The  quantity  of  nitrogen  is  nearly  the   same  in  the 
expired  as  in  the  inspired  air. 

Observation.     It  is  now   fully  ascertained  that  while  the 
chemical  composition  of  the  blood  is  essentially  changed,  its 

495 — 546.  Give  the  hygiene  of  the  respiratory  organs.  495.  "What  ia 
necessary  that  man  enjoy  the  highest  degree  of  health?  496.  How  does 
the  volume  of  expired  air  compare  with  that  which  was  inspired?  Does 
this  loss  vary,  and  what  is  an  average  estimate  ?  497.  How  is  the  purity 
of  the  air  affected  by  respiration  ?  How  is  the  inhaled  oxygen  affected  ? 
What  effect  on  the  carbonic  acid  and  watery  vapor  ?  On  the  nitrogen  ? 
What  is  said  respecting  the  weight  of  the  blood  ? 


HVMKXK    OF    THE    RESPIRATORY    tiRP.AiNS.  2"J9 

weight  remains  the  same,  as  the  carbon  and  hydrogen  dis- 
rharged  are  equal  to  the  united  weight  of  the  oxygen  and 
nitrogen  absorbed. 

498.  If  one  fourth  part  of  the  volume  of  air  received  by 
the  lungs  at  one  inspiration  is  decomposed  at  one  "  beat " 
of  the  heart,  it  might  be  supposed  that  if  the  expired  air  be 
again  received  into  the  lungs,  one  half  of  the  oxygen  would 
be  consumed,  and,  in  a  similar  ratio,  if  re-breathed  four  times, 
all  the  oxygen  would  be  consumed.     But  it  does  not  follow,  if 
the  air  is   thus  re-breathed,  that   the  same   changes  will  be 
effected  in  the  lungs.     For  air  that  has  been  inspired  does 
not  part  with  its  remaining  oxygen  as  freely  as  when  it  con- 
tains the  proper  amount  of  this  life-giving  element,  and  thus 
the  changes  in  the  impure  blood  are  not  so  completely  effected. 

Illustration.  In  the  process  of  dyeing,  each  successive 
article  immersed  in  the  dye  weakens  it ;  but  it  does  not 
follow  that  the  dye  each  time  is  affected  in  the  same  degree, 
or  that  the  coloring  matter  by  repeated  immersions  can  be 
wholly  extracted.  The  same  principle  applies  to  the  exchange 
of  oxygen  and  carbonic  acid  gas  in  the  lungs. 

499.  If  the  inspired  air  is  free  from  moisture  and  carbonic 
acid,  these  substances  contained  in  the  Hood  will  be  more 
readily  imparted  to  it.    When  the  air  is  loaded  with  vapor,  they 
are  removed  more  slowly ;  but  if  it  is  saturated  with  moisture, 
no  vapor  will  escape  from  the  blood  through  the  agency  of  the 
lungs.     This  may  be  illustrated  by  the  following  experiment : 
Take  two  and  a  half  pounds  of  water,  add  to  it  half  a  pound  of 
nommon  salt,  (chloride  of  sodium,)  and  it  will  readily  mix 
with  the  water  ;  and  to  this  solution  add  the  same  quantity  of 
salt,  and  it  will  be  dissolved  more  slowly.     Again,  add  more 
salt,  and  it  will  remain  undissolved,  as  the  water  has  become 
saturated  by  the  pound  before  dissolved. 

498.  Does  air  that  is  re-breathed  freely  impart  its  oxygen  ?  Why  ? 
199.  What  is  the  effect  on  the  blood  when  the  air  is  free  from  vapor  ami 
-arbonic  acid  ?  When  londerl  with  vapor  ?  When  saturated  ?  Hoiv  is  this 
lllistraf.-l  ? 

•20 


230  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

500.  The  principle  in  this  experiment  is  analogous  to  that 
of  the  union  between  carbonic  gas  and  atmospheric  air. 
Allen  and  Pepy  showed  by  experiment,  that  air  which  had 
been  once  breathed,  contained  eight  and  a  half  per  cent,  of 
carbonic  acid.  They  likewise  showed,  that  no  continuance  of 
the  respiration  of  the  same  air  could  make  it  take  up  more 
than  ten  per  cent.  This  is  the  point  of  saturation. 

Experiment.  Sink  a  glass  jar  that  has  a  stop-cock,  or  one 
with  a  glass  stopper,  into  a  pail  of  water,  until  the  air  is  expelled 
from  the  jar.  Fill  the  lungs  with  air,  and  retain  it  in  the 
chest  a  short  time,  and  then  breathe  into  the  jar,  and  instantly 
close  the  stop-cock.  Close  the  opening  of  the  jar  that  is  under 
the  water  with  a  piece  of  paper  laid  on  a  plate  of  sufficient 
size  to  cover  the  opening,  invert  the  jar,  and  sink  into  it  a 
lighted  candle.  The  flame  will  be  extinguished  as  quickly 
as  if  put  in  water.*  Remove  the  carbonic  acid  by  inverting 
the  jar,  and  place  a  lighted  candle  in  it,  and  the  flame  will  be 
as  clear  as  when  out  of  the  jar. 

Observations.  1st.  It  is  familiarly  known  that  a  taper  will 
not  burn  where  carbonic  acid  exists  in  any  considerable 
quantity,  or  when  there  is  a  marked  deficiency  of  oxygen. 
From  this  originated  the  judicious  practice  of  sinking  a  lighted 
candle  into  a  well  or  pit  before  descending  into  it.  If  the 
flame  is  extinguished,  respiration  cannot  there  be  maintained, 
and  life  would  be  sacrificed  jshould  a  person  venture  in,  until 
llie  noxious  air  is  removed. 

2d.  It  is  the  action  of  carbonic  acid  upon  the  respiratory 


*  As  a  substitute  for  a  jar  with  a  stop-cock,  take  a  piece  of  lead  pipe 
bent  in  the  form  of  a  siphon,  and  insert  it  in  the  mouth  of  »  reversed 
jar.  This  experiment  is  as  conclusive  whether  the  air  is  inhaled  once 
only  or  breathed  many  times. 

500.  What  did  the  experiments  of  A'len  and  Pepy  show  ?  How  can  the 
presence  of  carbonic  gas  in  the  expired  air  be  demonstrated  ?  State  obser- 
vation 1st.  Observation  2d. 


HYGIENE    OF    THE    RESPIRATORY    ORGANS.  X.j\ 

organs,  that  gives  rise  to  a  phenomenon  frequently  seen  m 
mines  and  caves.  A  man  may  enter  these  subterranean 
rooms,  and  feel  no  inconvenience  in  breathing ;  but  the  dog 
ihat  follows  him,  falls  apparently  dead,  and  soon  dies  if  not 
speedily  removed  to  pure  air.  This  arises  from  the  fact  that 
this  gas  is  heavier  than  air,  and  sinks  to  the  bottom  of  the 
room  or  cave. 

3d.  While  it  is  true  that  carbonic  acid  possesses  properties 
that  render  it  unfit  to  be  breathed,  it  is,  notwithstanding, 
productive  of  very  agreeable  effects,  when  conveyed  into 
the  stomach.  It  forms  the  sparkling  property  of  mineral 
waters,  and  fills  the  bubbles  that  rise  when  beer  or  cider  is 
fermenting. 

501.  Pure  atmospheric  air  is  lest  adapted  to  a  healthy 
action  of  the  system.     As  the  air  cannot  be  maintained  pure 
under  all  circumstances,  the  question  may  be  asked,  To  what 
degree  may  the   air  be  vitiated  and  still  sustain  life  ?    and 
what  is  the  smallest  quantity  of  pure  air  a  person  needs  each 
minute  to  maintain  good  health  ?     Birnan  says,  that  air  which 
contains  more  than  three  and  a  half  per  cent,  of  carbonic 
acid  is  unfit  for  resoiration,  and,  as  air  once  respired  contains 
eight  and  a  half  per  cent,  of  carbonic  acid,  it  clearly  shows 
that  it  is  not  fitted  to  be  breathed  again. 

502.  No  physiologist  pretends  that  less  than  seven  cubic 
feet  of  air  are  adequate  for  a   man  to  breathe  each  minute, 
while  Dr.  Reid  allows  ten  feet.     The  necessity  of  fifteen   or 
twenty  times  the  amount  of  air  actually  taken  into  the  lungs, 
arises    from   the  circumstance,  that   the    expired    air    mixes 
with  and  vitiates  the  surrounding  element  that  has  not  been 
inhaled. 

503.  The  quantity  of  air  which  different  persons  actually 

Observation  3d.  501.  What  questions  may  be  asked  respecting  the 
inspired  air?  Give  the  remark  of  Birnan.  502.  How  many  cubic  feet  of 
air  are  adequate  for  a  man  to  breathe  each  minute  ?  How  much  does  Dr. 
Iloid  allow?  503.  Mention  some  reasons  why  different  persons  do  not 
require  the  same  amount  of  air 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

need,  varies.  The  demand  is  modified  by  the  size,  a^e, 
habits,  and  condition  of  the  body.  A  person  of  great  size 
who  has  a  large  quantity  of  blood,  requires  more  air  than  a 
small  man  with  a  less  amount  of  circulating  fluid.  Individuals 
whose  labor  is  active,  require  more  air  than  sedentary  or  idle 
persons,  because  the  waste  of  the  system  is  greater.  On  the 
same  principle,  the  gormandizer  needs  more  of  this  element 
than  the  person  of  abstemious  habits.  So  does  the  growing 
lad  require  more  air  than  an  adult  of  the  same  weight,  for 
the  reason  that  he  consumes  more  food  than  a  person  of 
mature  years.  Habit  also  exerts  a  controlling  influence.  A 
man  who  works  in  the  open  air  suffers  more  when  placed  in 
a  small,  unventilated  room,  than  one  who  is  accustomed  to 
breathe  the  confined  air  of  workshops. 

504.  Air^  in  which  lamps  will  not  burn  with  brilliancy,  is 
unfitted  for  respiration.  In  crowded  rooms,  which  are  not 
ventilated,  the  air  is  vitiated,  not  only  by  the  abstraction  of 
oxygen  and  the  deposition  of  carbonic  acid,  but  by  the  excre- 
tions from  the  skin  and  lungs  of  the  audience.  The  lamps, 
under  such  circumstances,  emit  but  a  feeble  light.  Let  the 
oxygen  gas  be  more  and  more  expended,  and  the  lamps  will 
burn  more  and  more  feebly,  until  they  are  extinguished. 

Illustrations.  1st.  The  effects  of  breathing  the  same  air 
again  and  again,  are  well  illustrated  by  an  incident  that 
occurred  in  one  of  our  halls  of  learning.  A  large  audience 
had  assembled  in  an  ill-ventilated  room,  to  listen  to  a  lecture  ; 
soon  the  lamps  burned  so  dimly  that  the  speaker  and  audience 
were  nearly  enveloped  in  darkness.  The  oppression,  diz 
ziness,  and  faintness  experienced  by  many  of  the  audience 
induced  them  to  leave,  and  in  a  few  minutes  after,  the  lamps 
were  observed  to  rekindle,  owing  to  the  exchange  of  pure  air 
on  opening  the  door. 

How  Is  it  with  the  laborer  ?  With  the  gormandizer  ?  With  the  person 
that  wf  rks  in  the  open  air  ?  504.  What  effect  has  impure  air  on  a  burning 
lamp  ?  Give  the  illustration  of  the  effects  of  impure  air  on  lighted  lamps 


HYUIENE    OF    THE    RESPIRATORY    ORGANS.  233 

2d.  In  the  "Black  Hole  of  Calcutta,"  one  hundred  and 
forty-six  Englishmen  were  shut  up  in  a  room  eighteen  feel 
square,  with  only  two  small  windows  on  the  same  side  to  admit 
air.  On  opening  this  dungeon,  ten  hours  after  their  imprison- 
ment, only  twenty-three  were  alive.  The  other*  had  died 
from  breathing  impure  air. 

505.  Air  that  has  become  impure  from  the  abstraction  of 
oxygen,  an  excess  of  carbonic  acid,  or  the  excretions  from  (he 
lungs  and  skin,  has  a  deleterious  effect  on  the  body.     When 
this  element  is  vitiated  from  the  preceding  causes,  it  prevents 
the  proper  arterialization,  or  change   in  the  blood.     For  this 
reason,  pure  air  should  be  admitted  freely  and  constantly  into 
work-shops  and  dwelling-houses,  and  the  vitiated  air  permitted 
to  escape.     This  is  of  greater  importance  than  the  warming 
of  these  apartments.     We  can  compensate  for  the  deficiency 
of  a  stove,  by  an  extra  garment  or  an  increased  quantity  of 
food  ;  but  neither  garment,  exercise,  nor  food  will  compensate 
for  pure  air. 

506.  School-rooms  should  be  ventilated.     If  they  are  not, 
the  pupils  will  be  restless,  and  complain  of  languor  and  head- 
ache.    These  unpleasant  sensations  are  caused  by  a  want  of 
pure  air,  to  give  an  adequate  supply  of  oxygen  to  the  lungs. 
When  pupils  breathe  for  a  series  of  years  such  vitiated  air, 
their  life  is  undoubtedly  shortened,  by  giving  rise  to  consump 
tion  and  other  fatal  diseases. 

Illustration.  A  school-room  thirty  feet  square  and  eight 
feet  high,  contains  7200  cubic  feet  of  air.  This  room  will 
seat  sixty  pupils,  and,  allowing  ten  cubic  feet  of  air  to  each 
pupil  per  minute,  all  the  air  in  the  room  will  be  vitiated  in 
twelve  minutes. 

Observation.   In  all  school-rooms  where  there  is  not  ade* 


Of  the  effects  of  breathing  impure  air.     505.  In  preserving  health,  what 
is  of  greater  importance  than  warming  the  room  ?      506.  Why  should  a 
school-room  be  ventilated  ?    Give  the  illustration. 
20  * 


5JJM  ANATOMY,    PHYSIOLOGY,    AMD    HYGIENE. 

quate  ventilation,  it  is  advisable  to  have  a  recess  of  five  or 
ten  minutes  each  hour.  During  this  time,  let  the  pupils 
breathe  fresh  air,  and  open  the  doors  and  windows,  so  tha.  the 
air  of  the  room  shall  be  completely  changed. 

507.  Churches,  concert  halls,  and  all  rooms  designed  for 
a  collection  of  individuals,  should  be  amply  ventilated.     While 
the  architect  and  workmen  are  assiduous  in  giving  these  public 
rooms  architectural    beauty  and   splendor,   by  adorning    the 
ceiling  with  Gothic  tracery,  rearing  richly  carved  columns, 
and  providing  carefully  for  the  warming  of  the   room,  it  too 
frequently  happens  that  no  direct  provision  is  made  for  the 
change  of   that   element   which    gives  us    beauty,   strength, 
and  life. 

Illustration.  A  hall  sixty  feet  by  forty,  and  fifteen  feet 
high,  contains  36,000  cubic  feet  of  air.  A  hall  of  this  size 
will  seat  four  hundred  persons;  by  allowing  ten  cubic  feet  of 
air  to  each  person  per  minute,  the  air  of  the  room  will  be 
rendered  unfit  for  respiration  in  nine  minutes. 

508.  Railroad  cars,  cabins  of  steam  and  canal-boats,  omni- 
buses, and  stage-coaches,  require  ample  ventilation.     In  the 
construction  of  these  public  conveyances,  too  frequently,  the 
only  apparent  design  is,  to  seat  the  greatest  number  of  persons, 
regardless  of  the  quantity  and  character  of  the  air  to  maintain 
health  and  even  life.     The  character  of  the  air  is  only  realized 
when,  from  the  fresh,  pure  air,  we  enter  a  crowded  cabin  of 
a  boat  or  a  closed  coach ;  then  the  vitiated  air  from  anima] 
excretions  and  noxious  gases  is  offensive,  and  frequently  pro- 
duces sickness. 

509.  The    influence    of    habit   is  strikingly  expressed  by 
Birnan,  in  the  "  Art  of  Warming  and  Ventilating   Rooms  :  " 
"  Not  the  least  remarkable  exarr^e  of  the  power  of  habit  is 

What  suggestion  when  a  school-room  is  not  ventilated  ?  507.  "What  is 
said  in  regard  to  ventilating  churches,  concert  halls,  &c.  ?  State  the 
illustration.  508.  What  remarks  relative  to  public  conveyances  ?  509.  State 
the  influence  of  habit  by  Birnan. 


HYGIENE  OF  THE  RESPIRATORY  ORGANS.        235 

vfci  reconciling  us  to  practices  which,  but  for  its  influence, 
would  be  considered  noxious  and  disgusting.  We  instinctively 
shun  approach  to  the  dirty,  the  squalid,  and  the  diseased,  and 
use  no  garment  that  may  have  been  worn  by  another.  We 
open  sewers  for  matters  that  offend  the  sight  or  the  smell,  and 
contaminate  the  air.  We  carefully  remove  impurities  from 
what  we  eat  arid  drink,  filter  turbid  water,  and  fastidiously 
avoid  drinking  from  a  cup  that  may  have  been  pressed  to  the 
lips  of  a  friend.  On  the  other  hand,  we  resort  to  places  of 
assembly,  and  draw  into  our  mouths  air  loaded  with  effluvia 
from  the,  lungs,  skin,  and  clothing  of  every  individual  in  the 
promiscuous  crowd  —  exhalations  offensive,  to  a  certain  extent, 
from  the  most  healthy  individuals ;  but  when  arising  from  ?\ 
living  mass  of  skin  and  lungs,  in  all  stages  of  evaporation, 
disease,  and  putridity,  —  prevented  by  the  walls  and  ceiling 
from  escaping, — they  are,  when  thus  concentrated,  in  the 
highest  degree  deleterious  and  loathsome." 

510.  The  sleeping-room  should  be  so  ventilated  that  the  air 
in  I  he  morning  will  be  as  pure  as  when  retiring  to  rest  in  the 
evening.  Ventilation  of  the  room  would  prevent  morning 
headaches,  the  want  of  appetite,  and  languor  —  so  common 
among  the  feeble.  The  impure  air  of  sleeping-rooms  proba- 
bly causes  more  deaths  than  intemperance.  Look  around  the 
country,  and  those  who  are  most  exposed,  who  live  in  huts 
but  little  superior  to  the  sheds  that  shelter  the  farmer's  flocks, 
are  found  to  be  the  most  healthy  and  robust.  Headaches,  liver 
complaints,  coughs,  and  a  multitude  of  nervous  affections,  are 
almost  unknown  to  them ;  not  so  with  those  who  spend  their 
days  and  nights  in  rooms  in  which  the  sashes  of  the  windows 
are  calked,  or  perchance  doubled,  to  prevent  the  keen  but 
healthy  air  of  winter  from  entering  their  apartments.  Disease 
ar.d  suffering  are  their  constant  companions. 


SIO.  What  is  said  of  the  ventilation  of  sleeping-rooms  ?     What  would 
adequate  ventilation  prevent  ?     Give  a  common  observation. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

Illustration.  By  many,  sleeping  apartments  twelve  feet 
square  and  seven  feet  high,  are  considered  spacious  for  two 
persons,  and  good  accommodations  for  four  to  lodge  in.  An 
apartment  of  this  size  contains  1008  cubic  feet  of  air.  Al* 
lowing  ten  cubic  feet  to  each  person  per  minute,  two  occupants 
would  vitiate  the  air  of  the  room  in  fifty  minutes,  and  four  in 
twenty-five  minutes.  When  lodging- rooms  are  not  ventilated, 
we  would  strongly  recommend  early  rising. 

511.  The  sick-room,  particularly,  should  be  so   arranged 
that  the  impure  air  may  escape,  and  pure  air  be  constantly  ad- 
mitted into  the  room.     It  is  no  unusual  practice  in  some  com- 
munities, when  a  child  or  an  adult  is  sick  of  an  acute  disease, 
to  prevent  the  ingress  of  pure  air,  simply  from  the  apprehen- 
sion of  the  attendants,  that  the  patient  will  contract  a  cold. 
Again,  the  prevalent  custom  of  several  individuals  sitting  in 
the  sick-room,  particularly  when  they  remain  there  for  several 
hours,  tends  to  vitiate  the  air,  and,  consequently,  to  increase 
the  suffering  and   danger  of  the  sick  person.     In  fevers  or 
inflammatory   diseases  of  any  kind,  let  the  patient  breathe 
pure  air;  for  the  purer  the  blood,  the  greater  the  power  of  the 
system  to  remove   disease,  and  the  less  the  liability  to  con- 
tract colds. 

Observation.  Among  children,  convulsions,  or  "  fits,"  usu- 
ally occur  when  they  are  sleeping.  In  many  instances,  these 
are  produced  by  the  impure  air  which  is  breathed.  To  pre- 
vent these  alarming  and  distressing  convulsions,  the  sleeping- 
room  should  be  ventilated,  and  there  should  be  no  curtain? 
around  the  bed,  or  coverings  over  the  face,  as  they  produce 
an  effect  similar  to  that  experienced  when  sleeping  in  a  small, 
unventilated  room.  To  relieve  a  child  when  convulsed,  carry 
't  into  the  open  air. 

512.  While  occupying  a   room,  we  are  insensible  of  the 

What  is  said  of  the  size  of  sleeping-rooms?  511.  What  is  said  of  the 
sick-room  ?  Mention  some  prevailing  customs  in  reference  to  these 
rooms  What  is  sa>-l  of  convulsions  among  children? 


HYGIENE  OF  THE  RESPIRATORY  ORGANS.        237 

gradual  vitiation  of  the  air.  This  is  the  result  of  the  dimin- 
ished sensibility  of  the  nervous  system,  and  gradual  adaptation 
of  the  organs  to  blood  of  a  less  stimulating  character.  This 
condition  is  well  illustrated  in  the  hibernating  animals.  We 
are  insensible  of  the  impure  air  of  unventilated  sleeping-rooms, 
until  we  leave  them  for  a  walk  or  ride.  If  they  have  been 
closed,  we  are  made  sensible  of  the  character  of  the  air  as 
soon  as  we  reenter  them,  for  the  system  has  regained  its  usual 
sensibility  while  inhaling  a  purer  atmosphere. 

513.  In  the  construction   of  every  inhabited  room,  there 
should  be  adequate  means  of  ventilation,  as  well  as  warming. 
No  room  is  well  ventilated,  unless  as  much  pure  air  is  brought 
into  it  as  the  occupants  vitiate  at  every  respiration.     This  can 
be  effected  by  making  an  aperture  in  the  ceiling  of  the  room, 
or  by  constructing  a  ventilating  flue   in  the  chimney.     This 
should  be  in  contact  with  the  flues  for  the  escape  of  smoke, 
but  separated  from  them  by  a  thin  brick  partition.     The  hot 
air  in  the  smoke  flues  will  warm  the  separating  brick  partition, 
and  consequently  rarefy  the  air  in  the  ventilating  flue.     Com- 
munication from  every  room  in  a  house  should  be  had  to  such 
flues.     The  draught  of  air  can  be  regulated  by  well-adjusted 
registers,  which  in  large  rooms  should  be  placed  near  the  floor 
as  well  as  near  the  ceiling. 

514.  While   provision  is  made  for  the  escape  of  rarefied 
impure  air,  we  should  also  provide  means  by  which  pure  air 
may  be  constantly  admitted  into  the  room,  as  the  crevices  of 
the  doors  and  windows  are  not  always  sufficient ;  and,  if  they 
should  be  adequate,  air  can  be  introduced  in  a  more  conven- 
ient, economical,  and  appropriate  manner.     There  should  be 
an  aperture  opposite  the  ventilating  flue,  at  or  near  the  floor, 
to  connect  with  the  outer  walls  of  the  building  or  external  air 

512.  Why  are  we  insensible  to  the  gradual  vitiation  of  the  air  of  an  un 
ventilated  room  ?  513.  What  is  very  important  in  the  building  of  every 
inhabited  room  ?  How  can  a  room  be  well  ventilated  ?  514.  What  is  said 
relative  to  a  communication  with  the  external  air  ? 


238  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

But  if  pure  heated  air  is  introduced  into  the  room,  it  obvistes 
the  necessity  of  the  introduction  of  the  external  air.* 

5*lix  Jit  waianing  rooms,  the  hot  air  furnaces,  or  box  and 
air-tight  stoves^  converted  into  hot  air  furnaces,  should  be 
used  in  preference  to  the  ordinary  stoves.  The  air  thus  intro 
duced  into  the  room  is  pure  as  well  as  warm.  In  the  adapta 
tion  of  furnaces  to  dwelling-houses,  &c.,  it  is  necessary  tha 
the  air  should  pass  over  an  ample  surface  of  iron  moderatelj 
heated ;  as  a  red  heat  abstracts  the  oxygen  from  the  contigu 
ous  air,  and  thus  renders  it  unfit  to  be  respired.t 

Observation.  Domestic  animals  need  a  supply  of  pure  ah 
as  well  as  man.  The  cows  of  cities,  that  breathe  a  vitiated 
air,  have,  very  generally,  tubercles.  Sheep  that  are  shut  in 
a  confined  air,  die  of  a  disease  called  the  "  rot,"  which  is  of 
a  turberculous  character.  Interest  and  humanity  require  thai 
the  buildings  for  animals  be  properly  ventilated. 


*  Mr.  Frederick  Emerson,  of  Boston,  has  devised  a  simple  and 
effective  apparatus  for  removing  vitiated  air  from  a  room.  It  is  suc- 
cessfully used  upon  all  the  public  school-houses  of  Boston.  It  is  now 
being  generally  applied  to  the  school-houses  and  other  public  build- 
ings, as  well  as  private  dwellings,  of  New  England. 

f  Dr.  Wyman's  valuable  work  on  "  Ventilation,"  and  the  work  of 
Henry  Barnard,  Esq.,  on  "School-house  architecture,"  can  be  advanta- 
geously consulted,  as  they  give  the  practical  methods  of  ventilating 
and  warming  shops,  school-rooms,  dwelling-houses,  public  halls,  &c. 

515.  How  should  rooms  be  warmed  ?  What  is  necessary  in  the  adapta- 
tion  of  furnaces  to  dwelling-houses  ? 


HYGIENE  OF  THE  RESPIRATORY  ORGANS. 

Xj 

CHAPTER     XX 

HYGIENE  OF  THE  RESPIRATORY  ORGANS,  CONTINUE!). 

516.  THE  change  that  is  effected  in  the  blood  while  passing 
through  the  lungs,  not  only  depends  upon  the  purity  of  the 
air,  but  the  amount  inspired.     The  quantity  varies  according 
to  the  size  of  the  chest,  and  the  movement  of  the  ribs  and 
diaphragm. 

517.  The  size  of  the  chest  and  lungs  can  be  reduced  by 
moderate  and  continued  pressure.     This  is  most  easily  done 
in  infancy,  when  the  cartilages  and  ribs  are  very  pliant ;  yet 
it  can  be  effected  at  more  advanced  periods  of  life,  even  after 
the  chest  is  fully  developed.     For  want  of  knowledge  of  the 
pliant  character  of  the  cartilages  and  ribs  in  infants,  too  many 
mothers,  unintentionally,  contract  their  chests,  and  thus  sow 
the  seeds  of  disease  by  the  close  dressing  of  their  offspring. 

518.  If  slight  but  steady  pressure  be  continued  from  day 
to  day  and  from  week  to  week,  the  ribs  will  continue  to  yield 
more   and  more,  and  after  the  expiration  of  a  few  months, 
the   chest  will   become    diminished    in   size.     This   will    be 
effected  without  any  suffering  of  a  marked  character;  but 
the  general  health  and  strength  will  be  impaired.     It  is  not 
the   violent  and   ephemeral  pressure,  but  the  moderate  and 
protracted,   that   produces    the    miscalled,  "  genteel,"    con- 
tracted chests. 

519.  The  style  of  dress  which  at  the  present  day  is  almost 
universal,  is  a  prolific  cause  of  this  deformity.     These  bane- 

616.  What  varies  the  amount  of  air  received  into  the  lungs  ?  517.  How 
can  the  size  of  the  chest  be  diminished  ?  When  is  this  most  easily  effected  ? 
618.  How  are  the  miscalled,  "  genteel,"  contracted  chests  usually  pro- 
duced ?  519.  What  is  said  of  the  style  of  the  dress  at  the  present  day  ? 


2-10  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

ful  fashions  are  copied  from  the  periodicals,  so  widely  cif 
culated,  containing  a  "fashion  plate  of  the  latest  fashions, 
from  Paris."  In  every  instance,  the  contracted,  deformed, 
and,  as  it  is  called,  lady-like  waist,  is  portrayed  in  all  its 
fascinating  loveliness.  These  periodicals  are  found  on  almost 
every  centre-table,  and  exercise  an  influence  almost  omnip- 
otent. If  the  plates  which  corrupt  the  morals  are  excluded 
by  civil  legislation,  with  the  same  propriety  ought  not  those  to 
be  suppressed  that  have  a  tendency  so  adverse  to  health  ? 


100.  Fig.  101. 


r  ig.  100.  A  correct  outline  of  the  Venus  de  Medici,  the  beau  ideal  of  female 
'/muielry. 

Fig.  101.    An  outline  of  a  well-corseted  modern  beauty. 

One  has  an  artificial,  insect  waist ;  the  other,  a  natural  waist.  One  has  sloping 
shoulders,  while  the  shoulders  of  the  other  are  comparatively  elevated,  square,  and 
angular.  The  proportion  of  the  corseted  female  below  the  waist,  is  also  a  departure 
from  the  symmetry  of  nature. 

Observations.     1st.    The  Chinese,  by  compressing  the  feet 
of  female  children,  prevent  their  growth ;  so  that  the  foot  of  a 

What  does  fig.  100  represent  ?    Fig.  101  ?    Give  observation  1st 


HYGIENE    01     I  HI     REbtlhAroKY    OflliAivS.  2ii 

Chinese  belle  is  not  larger  than  the  foot  of  an  American  giii 
of  five  years. 

2d.  The  American  women  compress  their  chests^  to  prevent 
their  growth  ;  so  that  the  cnest  of  an  American  belle  is  nut 
larger  than  the  chest  of  a  Chinese  girl  of  five  years.  Which 
country,  in  this  respect,  exhibits  the  greater  intelligence  ? 

3d.  The  chest  can  be  deformed  by  making  the  linings  of 
the  waists  of  the  dresses  tight,  as  well  as  by  corsets.  Tight 
vests,  upon  the  same  principle,  are  also  injurious. 

520.  In  children,  who  have    never  worn  close  garments, 
l"ie  circumference  of  the  chest  is  generally  about  equal  to  that 
of  the  body  at  the  hips  ;  and  similar  proportions  would  exist 
through    life,    if  there    were    no    improper   pressure   of  the 
clothing.     This  is  true  of  the  laboring  women  of  the  Emerald 
Isle,  and  other  countries  of  Europe,  and  in  the  Indian  female, 
whose  blanket  allows  the  free  expansion  of  the  chest.     The 
symmetrical   statues  of  ancient   sculptors    bear   little   resem- 
blance to  the  "  beau  ideal "  of  American  notions  of  elegant 
form.     This   perverted  taste  is  in  opposition  to  the  laws  of 
nature.     The   design  of  the  human  chest  is  not  simply  to 
connect  the  upper  and  lower  portions  of  the  body,  like  some 
insects,   but  to   form  a  case  for  the   protection  of  the  vital 
o  gans. 

521.  Individuals  may  have  small  chests  from  birth.     This, 
to  the  particular  individual,  is  natural ;  yet  it  is  adverse  to  the 
great  and  general  law  of  Nature  relative  to  the  size  of  the 
human  chest.     Like  produces  like,  is  a  general  law  of  the 
animal   and   vegetable    kingdoms.     No  fact   is  better  estab- 
lished, than   that  which   proves  the   hereditary  transmission 


Observation  2d.  Observation  3d.  520.  What  is  the  size  of  the  chest  of 
a  child  that  has  always  worn  loose  clothing  ?  What  is  said  of  the  size  of 
the  laboring  women  of  Ireland,  and  the  Indian  female?  How  is  it  in 
ancient  statues  ?  What  is  the  design  of  the  chest?  -521.  What  is  a  gen- 
eral law  of  both  the  animal  and  vegetable  kingdoms  ?  What  fact  in  this 
connection  is  well  established  ? 
21 


242  ANATOMY,    PH^biOLOGY,    AiS  D    HYGIENE. 

from  parents  to  children  of  a  constitutional  liability  to  diseasf 
and  the  same  may  be  said  m  regard  to  their  conformations 
If  the  mother  has  a  small,  taper  waist,  either  hereditary  or 
acquired,  this  form  may  be  impressed  on  her  offspring  ;  —  thus 
illustrating  the  truthfulness  of  scripture,  "  that  the  sins  of  the 
parents  shall  be  visited  upon  the  children  unto  the  third  and 
fourth  generation." 

522.  The  quantity  of  air  inhaled  is  modified  by  the  capa- 
city of  the  respiratory  organs.     The  necessity  of  voluminous 
lungs  may  be  elucidated  by  the  following  experiment :    Sup- 
pose a  gill  of  alcohol,  mixed  with  a  gill  of  water,  be  put  into 
a  vessel  having  a  square  foot  of  surface,  and  over  the  vessel 
a  membrane  be   tied,  and  that  the  water  will   evaporate  in 
twenty-four  hours.     If  the  surface  had  been  only  six  inches 
square,  only  one  fourth  of  the  water  would  have  evaporated 
through  the  membrane  in  the  given  time.     If  the  surface  had 
been  extended  to  two  square  feet,  the  water  would  have  evap- 
orated in  twelve  hours. 

523.  Apply  this  principle  to  the  lungs :  suppose  there  are 
two  hundred  feet  of  carbonic  acid   to  be  carried  out  of  the 
system  every  twenty-four  hours.     This  gas,  in  that  time,  will 
pass  through  a  vesicular  membrane  of  two  thousand  square 
feet.    If  the  lungs  were  diminished  hi  size,  so  that  there  would 
be  only  one  thousand  square  feet  of  vesicular  membrane,  the 
amount  of  carbonic  acid  would  not,  and  could  not,  be  eliminated 
from  the  system.     Under  such  circumstances,  the  blood  would 
not  be  purified. 

524.  Again ;  suppose  the    two   thousand    square    feet    oi 
nvsmbrane  would  transmit  two  hundred  cubic  feet  of  oxygen 
into  the   system   every  twenty-four    hours.     If  it  should  be 
diminished  one  half,  this  amount  of  oxygen  would  not  pass 
into  the   blood.     From  the  above  illustrations  we  may  learn 

What  does  this  hereditary  transmission  prove  ?  522.  How  is  the 
necessity  of  voluminous  lungs  illustrated  ?  523.  How  is  this  principle 
applied  to  the  interchange  of  products  in  the  lungs  ? 


IlYdlilNK    OF    THE    RESiJlKATOxiY    ORGANS.  213 

ihe  importance  of  well-developed  chests  and  voluminous 
lungs;  for,  by  increasing  the  size  of  the  lungs,  the  oxygen  is 
more  abundantly  supplied  to  the  blood,  and  this  fluid  is  more 
perfectly  deprived  of  its  carbon  and  hydrogen. 

525.  The  chest  is  not  only  most  expanded  at  its  lower 
part,  but  the  portion  of  the  lungs  that  occupies  this  space  of 
the  thoracic  cavity  contains  the  greater  part  of  the  air-cells ; 
and,  from  the  lower  two  thirds  of  the  lungs  the  greatest 
amount  of  carbonic  acid  is  abstracted  from  the  blood,  and 
the  greatest  amount  of  oxygen  gas  is  conveyed  into  the  cir- 
culating fluid.  Hence,  contracting  the  lower  ribs  is  far  more 
injurious  to  the  health  than  diminishing  the  size  of  the  upper 
part  of  the  chest. 

528.  The  question  is  often  asked,  Can  the  size  of  the  chest 
and  the  volume  of  the  lungs  be  increased,  when  they  have 
been  injudiciously  compressed,  or  have  inherited  this  un- 
natural form  ?  The  answer  is  in  the  affirmative.  The  means 
for  attaining  this  end  are,  a  judicious  exercise  of  the  lunga, 
by  walking  in  the  open  air,  reading  aloud,  singing,  sitting  erect, 
and  fully  inflating  the  lungs  at  each  act  of  inspiration.  If  the 
exercise  be  properly  managed  and  persevered  in,  it  will 
expand  the  chest,  and  give  tone  and  health  to  the  important 
organs  contained  in  it.  But,  if  the  exercise  be  ill-timed  or 
carried  to  excess,  the  beneficial  results  sought  will  probably 
not  be  attained. 

Observation.  Scholars,  and  persons  who  sit  much  of  the 
time,  should  frequently,  during  the  day,  breathe  full  and 
deep,  so  that  the  smallest  air-cells  may  be  fully  filled  with 
air.  While  exercising  the  lungs,  the  shoulders  should  be 
thrown  back  and  the  head  held  erect. 

527.  The  movement  of  the  ribs  and  diaphragm  is  modified 
by  ihe  dress.  When  the  lungs  are  properly  filled  with  air, 

525.  Why  is  it  more  injurious  to  contract  the  lower  part  of  the  chest  than 
the  upper?  526.  How  can  the  size  of  the  chest  be  increased  when  it  is 
contracted?  (Jive  the  observation.  527.  How  is  the  movement  of  the 

ribs  u.u  1  ii<    .....  pa  modified  ? 


211  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

the  chest  is  enlarged  in  every  direction.  If  any  article  of 
apparel  is  worn  so  tight  as  to  prevent  the  full  expansion  of 
the  chest  and  abdomen,  the  lungs,  in  consequence,  do  not 
receive  air  sufficient  to  purify  the  blood.  The  effect  of  firm, 
unyielding  clothing,  when  worn  tight,  in  preventing  a  due 
supply  of  air  to  the  lungs,  may  be  shown  by  the  following 
illustration. 

Illustration.  If  the  diameter  of  a  circle  is  three  feet,  the 
circumference  will  be  nine  feet.  If  the  diameter  is  extended 
to  four  feet,  the  circumference  will  be  increased  to  twelve 
feet.  Should  a  tight  band  be  thrown  around  a  circle  of  nine 
feet,  its  diameter  cannot  be  increased,  for  the  circumference 
cannot  be  enlarged. 

528.  Any  inelastic  band,  drawn  closely  around  the   lower 
part  of  the  chest,  or  the  abdomen,  below  the  ribs,  operates 
like  the  band  in  the  preceding  illustration,  in  restricting  the 
movement  of  the  ribs.     When  any  article  of  dress  encircles 
either  the  chest  or  abdomen,  so  as  to  prevent  an  increase  of 
its  circumference,  it  has  an  injudicious  tendency,  as  it  pre- 
vents the  introduction  of  air  in -sufficient  quantities  to  purify 
the    blood.      The    question   is   not,    How    much     restriction 
of  the  respiratory  movements  can  be  endured,  and  life  con- 
tinue ?  but,  Does  any  part  of  the  apparel    restrict  the  move- 
ments ?     If  it  does,  it  is  a  violation  of  the  organic  laws  ;  and 
!  lough  Nature  is  profuse  in  her  expenditures,  yet  sooner  or 
later,  she  sums  up  her  account. 

529.  In  determining  whether  the  apparel  is  worn  too  tight, 
inflate  the  lungs,  and,  if  no  pressure  is  felt,  no  injurious  effects 
need  be  apprehended  from  this  cause.     In  testing  the  tight- 
ness of  the  dress,  some  persons  will  contract  to  the  utmost 
the    abdominal  muscles,  and  thus  diminish  the    size    of  the 

How  is  the  effect  of  unyielding  clothing,  when  worn  tight,  illustrated  '. 
528.  What  effect  has  an  inelastic  band  upon  the  lower  part  of  the  chest  ? 
What  question  is  asked  ?  529  How  can  we  determine  whether  the  apparel 
vs  worn  too  tight  ? 


HYGIENE    OF    THK    RF.STMRATORY    ORGANS.  IMC 

chest,  by  depressing  the  ribs ;  when  this  is  done,  the  in- 
dividual exclaims,  "  How  loose  my  dress  is  !  "  This  practice 
is  both  deceptive  and  ludicrous.  A  good  test  is,  to  put  the 
hand  on  the  chest  below  the  arm  ;  if  there  is  no  movement  of 
(he  ribs  during  respiration,  the  apparel  is  too  tight.  The  only 
reliable  test,  however,  is  a  full  inflation  of  the  lungs. 

Observation.  Many  individuals  do  not  realize  the  small 
amount  of  force  that  will  prevent  the  enlargement  of  tb^ 
chest.  This  can  be  demonstrated  by  drawing  a  piece  of  tape 
tightly  around  the  lower  part  of  the  chest  of  a  vigorous  adult, 
and  confining  it  with  the  thumb  and  finger.  Then  endeavoi 
fully  to  inflate  the  lungs,  and  the  movement  of  the  ribs  will 
be  much  restricted. 

530.  The  position  in  standing  and  sitting  influences  the 
movement  of  the  ribs  and  diaphragm.     When  the  shoulders 
are  thrown  back,  and  when  a  person  stands  or  sits  erect,  the 
diaphragm  and  ribs  have  more  freedom  of  motion,  and  the 
abdominal  muscles  act  more  efficiently  ;  thus  the  lungs   have 
broader  range  of  movement  than  when  the  shoulders  incline 
forward,  and  the  body  is  stooping. 

531.  Habit  exercises  an  influence  upon  the  range  of  the 
respiratory  movements.     A  person  who  has  been  habituated  to 
dress  loosely,  and  whose  inspirations  are  full  and  free,  suffers 
more  from  the  tightness  of  a  vest  or  waistband,  than  one,  the 
range  of  movements  of  whose  chest  has  long  been  subjected 
to  tight  lacing. 

532.  The  condition  of  the  brain  exercises  a  great  influence 
upon  respiration.     If  the    brain    is   diseased,    or   the    mind 
depressed   by   grief,  tormented  by  anxiety,  or   absorbed   by 
abstract  thought,  the  contractile  energy  of  the  diaphragm  and 

Give  another  test.  How  can  the  amount  of  pressure  necessary  to  pre- 
vent the  enlargement  of  the  chest  be  demonstrated  ?  530.  Show  tn* 
effect  of  position  on  the  movements  of  the  ribs  and  diaphragm.  531.  Sno-w 
the  effect  of  habit  on  the  respiratory  movements.  532.  State  the  influence 
of  the  mind  upon  respiration. 

21  * 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

that  elevate  the  ribs,  is  much  diminished,  and  the 
lungs  are  not  so  fully  inflated,  as  when  the  mind  is  influenced 
hy  joy  or  other  exhilarating  emotions.  The  depressing  pas- 
sions likewise  lessen  the  frequency  of  respiration.  By  the 
influence  of  these  causes,  the  blood  is  but  partially  punfied, 
and  the  whole  system  becomes  enfeebled.  Here  we  may 
see  the  admirable  harmony  between  the  different  parts  of 
(he  body,  and  the  adaptation  of  all  the  functions  to  each 
oilier. 

533.  As  the   quantity  of  air   inhaled   at  each    unimpeded 
inspiration  in  lungs  of  ample  size,  is  about  forty  cubic  inches, 
't    f  ilows,   if  the   movement  of  the   ribs    and  diaphragm   i*1 
restricted  by  an  enfeebled   action  of  the  respiratory  muscles, 
or  by  any  other  means,  the  blood  will  not  be  perfectly  purifif"1 
In  the  experiment,  (§  522,  523,)  suppose  forty  cubic  inches  of 
air  must  pass  over  the  membrane  twenty  times  every  minute, 
and   that    this  is  the  amount  .required  to  remove  the    vapoi 
which  arises  from  the  membrane  ;  if  only  half  of  this  amount 
of  air  be  supplied  each  minute,  only  one  half  as  much  water 
will  be  removed  from  the  alcohol  through  the   membrane  in 
twenty-four  hours ;  consequently,  the  alcohol  would  be  impure 
from  the  water  not  being  entirely  removed. 

534.  Restrain  the  elevation  of  the  ribs  and  depression  of 
the  diaphragm,  so  that  the  quantity  of  air  conveyed   into  the 
lungs  will  be  reduced  to  twenty  cubic  inches,  when  forty  are 
needed,  and  the  results  will  be  as  follows  :  Only  one  half  of 
the  carbonic  acid  will  be  eliminated  from  the  system,  and  the 
blood  will  receive  but  one  half  as  much  oxygen  as  it  requires 
This   fluid   will   then   be  imperfectly   oxydated,  and    partially 
fivoo   of  its   impurities.     The  impure  blood  will  be  returned 
to  the  H't  side  of  the  heart,  and  the  whole  system  will  sutler 
from  an  infringement  of  organic  laws. 

•~>33  Illustrate  the  effect  upon  the  Mood  when  the  respiratory  muscles 
are  enfeebled  in  their  action.  534.  Show  how  the  blood  is  impeiJectlj 
purified  by  restricting  the  movements  of  thu  ribs  and  diaphragm 


HYGIENE    OF    THE    RESPIRATORY    ORGANS.  .     247 

635.  Scrofula,  or  consumption,  frequently  succeeds  a  de 
pressed  statt  of  the  nervous  system.  These  diseases  arise 
from  the  deposition  of  tuberculous  matter  in  different  parts  of 
the  body.  Those  individuals  who  have  met  with  reverses  of 
fortune,  in  which  character  and  property  were  lost,  afford  pain- 
ful examples.  Hundreds  yearly  die  from  the  effect  of  depressed 
spirits,  caused  by  disappointed  hopes,  or  disappointed  ambi- 
tion. 

Illustration.  A  striking  instance  of  the  effects  of  mental 
depression  is  related  by  Lsennec.  In  a  female  religious 
establishment  in  France,  great  austerities  were  practised  ;  the 
mind  was  absorbed  in  contemplating  the  terrible  truths  of 
religion,  and  in  mortifying  the  flesh.  The  whole  establish- 
ment, in  the  space  of  ten  years,  was  several  times  depopu 
lated  —  with  the  exception  of  the  persons  employed  at  the 
gate,  in  the  kitchen,  and  garden  —  with  that  fatal  disease, 
consumption.  This  institution  did  not  long  continue,  but  was 
suppressed  by  order  of  the  French  government. 

536.  The  purity  of  the  blood  is  influenced  by  the  condition 
of  the  lungs.  When  the  bronchial  tubes  and  air-cells  have 
become  partially  impervious  to  air,  from  pressure  upon  the 
tungs,  from  fluids  in  the  chest,  from  tumors,  or  from  the  con- 
solidation of  the  cells  and  tubes  from  disease,  —  as  inflam- 
mation, or  the  deposition  of  yellow,  cheesy  matter,  called 
tubercles,  —  the  blood  will  not  be  purified,  even  if  the  air  is 
pure,  the  tungs  voluminous,  and  the  respiratory  movements 
unrestricted,  as  the  air  cannot  permeate  the  air-cells. 

Observations.  1st.  The  twenty-three  who  escaped  imme- 
diate death  in  the  Black  Hole  of  Calcutta  were  soon  attacked 
with  inflammation  of  the  lungs,  by  which  these  organs  were 

535.  Mention  some  of  the  effects  of  mental  depression  upon  the  body 
What  is  related  by  Laennec  ?  536.  Does  the  condition  of  the  lung^- 
influence  the  purity  of  the  blood  ?  Mention  some  of  the  conditions  that 
will  impede  the  oxydation  of  blood  in  the  lungs.  What  occurred  to  those 
persons  who  escaped  death  in  the  Black  Hole  of  Calcutta  ? 


Iil8    .  ANATOMY,    PHYSIOL'WV,    AND    TTYG1KNE. 

consolidated,  and  thus  prevented  the  permeation  of  air  into 
their  cells.  This  disease  of  the  lungs  was  caused  by  breath- 
ing vitiated  air. 

2d.  One  of  the  precursory  symptoms  of  consumption  is  the 
feeble  murmur  of  respiration  in  the  upper  part  of  the  lungs. 
This  condition  of  these  organs  is  produced  by,  or  frequently 
follows,  mental  depression,  the  breathing  of  impure  air,  the 
stooping  position  in  standing  or  sitting,  and  the  restriction  of 
the  movements  of  the  ribs  and  diaphragm. 

3d.  Persons  asphyxiated  by  carbonic  acid,  water,  stran- 
gling, or  any  noxious  air,  after  resuscitation,  are  usually  affected 
with  coughs  and  other  diseases  of  the  lungs. 

537.  COLDS  and  COUGHS  are  generally  induced  by  a  chill, 
that  produces  a  contraction   of  the  blood-vessels  of  the  skin  ; 
t»nd   the  waste   material,  which  should  be  carried   from  the 
body  by  the  agency  of    the   vessels  of    this    membrane,   is 
retained  in  the  system,  and  a  great  portion  of  it  is  returned  to 
the  mucous  membrane  of  the  lungs.     For  such  is  the  harmony 
established  by  the  Creator,  that  if  the  function  of  any  portion 
of  the  body  is  deranged,  those  organs  whose  offices  are  similar 
take  on  an  increased  action. 

538.  The  waste  material,  that  should  have  passed  through 
the  many  outlets  of  the  skin,  creates  an  unusual  fulness  of 
the  minute  vessels  that  nourish  the  mucous  membrane  of  the 
bronchia ;  this  induces  an  irritation  of  these  vessels,  which 
increases  the  flow  of  blood  to  the  nutrient  arteries  of  the  lungs. 
There  is,  also,  a  thickening  of  the  lining  membrane  of  the 
Jungs,  caused  by  the  repletion  of  the  bronchial  vessels  of  the 
mucous  membrane  ;  this  impedes  the  passage  of  air  through 
the  small   bronchial  tubes,  and   consequently  the  air-vesicles 

What  is  one  of  the  precursory  symptoms  of  consumption  ?  How  is  this 
condition  frequently  produced  ?  What  diseases  usually  follow  asphyxia  by 
c-.irbonic  a>cid,  water,  strangling,  £c.  ?  .537.  How  are  colds  generally  in- 
duced ?  538.  What  effect  has  a  common  cold  upon  the  mucous  membrane 
ol  the  lungs  ? 


HYG1ENK    OF    THE    RESPIRATORY    ORGANS.  '249 

cannot  impart  a  sufficient  quantity  of  oxygen  to  purify  the 
blood,  and  this  fluid,  imperfectly  purified,  does  not  pass  with 
facility  through  the  lungs.  An  additional  obstacle  to  the  free 
passage  of  air  into  the  lungs,  is  the  accumulation  of  blood  in 
the  pulmonary  vessels. 

539.  As  colds  and  coughs  are  very  generally  treated  by  the 
"  matrons  "  of  the  community,  or  by  the  patient,  the  following 
suggestions    may  aid    in    directing  a  proper  treatment :  To 
effect  a  speedy  cure,  it  is  necessary  to  diminish  the  amount  of 
fluid  in  the  vessels  of  the  lungs.     This  can  be  effected  in  two 
ways  :     1st.  By  diminishing  the  quantity  of  blood   in  the  sys- 
tem ;  2d.  By  diverting  it  from  the  lungs  to  the  skin.     The 
first  condition  can  be  easily  and  safely  affected,  by  abstaining 
from  food,  and  drinking  no  more  than  a  gill  of  fluid  in  twenty- 
four  hours.     As  there  is  a  continuous  waste   from  the  skin 
and  other  organs  of  the  system,  the  quantity  of  blood  by  this 
procedure  will   be   diminished,  and  the  lungs  relieved  of  the 
accumulated  fluid. 

540.  The  second  condition  can  be  accomplished  by  resort- 
ing to  the   warm  or  vapor  bath.      These  and  the   common 
sweats  will  invite   the  blood  from   the  lungs  to  the  skin.     By 
keeping  up  the  action  of  the  skin  for  a  few  hours,  the  lungs 
will  be  relieved.     In  some   instances,  emetics  and  cathartics 
are   necessary  ;    mucilages,  as   gum  arabic   or  slippery-elm 
bark,  would  be  good.     After  the  system  is  relieved,  the  skin 
is  more  impressible  to  cold,  and  consequently  requires  care- 
ful  protection   by   clothing.      In  good  constitutions,  the  first 
method    is    preferable,  and  generally  sufficient   without  any 
medicine  or  "  sweating." 

541.  The    method    of   resuscitating    persons    apparently 
drowned.     In   the  first  instance,  it  is  necessary  to  press  the 
chest,  suddenly  and   forcibly,  downward  and  backward,  and 


539.  Give  the  first  method  for  the  treatment  of  cold.    540.  The  second 
method.     541,542.  How  should    persons  apparently  drowned  be  treated? 


250  ANATOMY,    PHYSIOLOGY,    AND    IIVCIKN'E. 

instantly  discontinue  the  pressure.  Repeat  this  without  imor- 
mission,  until  a  pair  of  bellows  can  be  procured.  When  the 
bellows  are  obtained,  introduce  the  nozzle  well  upon  the  base 
of  the  tongue,  and  surround  the  mouth  and  nose  with  a  towel 
or  handkerchief,  to  close  them.  Let  another  person  press 
upon  the  projecting  part  of  the  neck,  called  "Adam's  apple,1 
while  air  is  introduced  into  the  lungs  through  the  bellows. 
Then  press  upon  the  chest,  to  force  the  air  from  the  lungs,  to 
imitate  natural  breathing.  (Appendix  M.) 

542.  Continue  the  use  of  the  bellows,  and  forcing  the  air 
out  of  the  chest,  for  an   hour  at  least,  unless  signs  of  natural 
breathing  come  on.     Wrap  the  body  in  warm,  dry  blankets, 
and  place  it  near  the  fire,  to  preserve  the  natural  warmth,  as 
well  as  to   impart  artificial  heat.     Every  thing,  however,  is 
secondary  to  filling  the   lungs  with  air.     Avoid  all   friction 
until  breathing  is  restored.    Send  immediately  for  medical  aid. 

543.  The  means  of  resuscitating  persons  asphyxiated  from 
electricity,  Sfc.     In   apparent  death   from   electricity,  (light- 
ning,) the  person  is  frequently  asphyxiated  from  pa-raly-sis 
(palsy)  of  the  respiratory  muscles.     To  recover  such  persons, 
resort  to  artificial  respiration.     In  cases  of  apparent  death 
from  hanging  or  strangling,  the  knot  should   be  untied  or  cut 
immediately  ;  then   use  artificial  respiration,  or  breathing,  as 
directed  in  apparent  death  from  drowning. 

Observation.  It  is  an  impression,  in  many  sections  of  the 
country,  that  the  law  will  not  allow  the  removal  of  the  cord 
from  the  neck  of  a  body  found  suspended,  unless  the  coroner 
be  present.  It  is  therefore  proper  to  say,  that  no  such  delay 
is  necessary,  and  that  no  time  should  be  lost  in  attempting 
to  resuscitate  the  strangled  person. 

544.  The  method  of  resuscitating  persons  apparently  dead 
from  inhaling  carbonic  acid  gas.     When   life  is  apparently 

•043.  What  treatment  should  be  adopted  in  asphyxia  from  elrrtriritv  ? 
From  hanging?  oil.  What  should  be  the  treatment  in  asphyxia  t'roir 
inhaling  r;ir!>.mir  ;u:id  ^a-;  r 


HYGIENE  OF  THE  RESPIRATORY  ORGANS.        251 

extinct  from  breathing  carbonic  acid  gas,  the  person  should 
be  carried  into  the  open  air.  The  head  and  shoulders  should 
be  slightly  elevated  ;  the  face  and  chest  should  be  sponged  or 
sprinkled  with  cold  water,  or  cold  vinegar  and  water,  while  the 
limbs  are  wrapped  in  dry,  warm  blankets.  In  this,  as  in 
asphyxia  from  other  causes,  immediately  resort  to  artificial 
respiration. 

Observations.  1st.  Many  persons  have  died  from  breathing 
carbonic  acid  that  was  formed  by  burning  charcoal  in  an  open 
pan  or  portable  furnace,  for  the  purpose  of  warming  their 
sleeping-rooms.  This  is  not  only  produced  by  burning  char- 
coal, but  is  evolved  from  the  live  coals  of  a  wood  fire  ;  and 
being  heavier  than  air,  it  settles  on  the  floor  of  the  room  ;  and, 
if  there  is  no  open  door  or  chimney-draught,  it  will  accumu- 
late, and,  rising  above  the  head  of  an  individual,  will  cause 
asphyxia  or  death. 

2d.  In  resuscitating  persons  apparently  dead  from  causes 
already  mentioned,  if  a  pair  of  bellows  cannot  be  procured 
immediately,  let  their  lungs  be  inflated  by  air  expelled  from 
the  lungs  of  some  person  present.  To  have  the  expired  air 
as  pure  as  possible,  the  person  should  quickly  inflate  his 
lungs,  and  instantly  expel  the  air  into  those  of  the  asphyxiated 
person.  Place  the  patient  in  pure  air,  admit  attendants 
only  into  the  apartment,  and  send  for  a  physician  without 
delay. 

"What  sad  results  frequently  follow  the  burning  of  charcoal  in  a  dosi 
room  ?  What  suggestion  in  resuscitating  asphyxiated  persons  ? 


ANATOMY.    PHYSIOLOGY.    AXI>    HY01F.NF.. 


CHAPTER    XXVII. 

ANIMAL    HEAT. 

645.  THE  true  sources  of  animal  heat,  or  calorification,  are 
still  imperfectly  known.  No  hypothesis  has,  as  yet,  receiver! 
the  concurrent  assent  of  physiologists.  We  see  certain  phe- 
nomena, but  the  ultimate  causes  are  hidden  from  our  view. 
Irs  regular  production,  to  a  certain  degree,  is  essential  both 
tc  animal  and  vegetable  life. 

546.  There  is  a  tendency  between  bodies  of  different  tem- 
perature to  an  equilibrium   of  heat.     Thus,  if  we  touch  or 
approach   a  hot   body,  the  heat,  or  caloric  passes  from  that 
body  to  our  organs  of  feeling,  and  gives  the  sensation  of  heat. 
On  the  contrary,  when  we  touch  a  cold  body,  the  heat  passes 
from  the  hand  to  that  body,  and  causes  a  sensation  of  cold. 

547.  The  greater  number  of  animals  appear  cold  when 
we  touch  them ;  and,  indeed,  the  temperature  of  their  bodies 
is  not  much  above  that  of  the  atmosphere,  and  changes  with 
it.     In   man,  and  other  animals   that  approach  him  in  their 
organization,  it  is   otherwise.     They  have  the  faculty  of  pro- 
ducing a  sufficient  quantity  of  caloric  to  maintain  their  tem- 
peratures nearly  at  the  same   degree,  under  all  atmospheric 
changes,  and  keep  themselves  warm. 

548.  Those  animals   whose   proper  heat   is  not  very  per 
ceivable,  are  called   coZrf-blooded ;  as  most  species  of  fishes, 
toads,  snakes,  turtles,  and   reptiles  generally.     Those  animals 

545 — 570.  What  is  said  respecting  animal  heat  f  545.  Are  the  true  sources 
of  animal  heat  known?  What  do  we  see?  546.  "What  is  the  tendency 
between  bodies  of  different  temperatur  js  ?  Give  an  explanation.  547.  What 
i«  said  of  the  temperature  of  animals  ?  548.  What  is  meant  by  cold-blooded 
animals  ?  13  •»  ^arm-blooded  animals  ? 


ANMMAL    ITK4T  > 

which  produce  sufficient  heat  independently  of  .ne  atmosphere 
surrounding  them,  are  called  warm-blooded ;  as  man,  birds, 
quadrupeds,  &c. 

549.  The  temperature  of  man  is  about  98°,  (Fahrenheit's 
thermometer,)  and  that  of  some  other  animals  is  higher ;  the 
temperature  of  birds,  for  example,  is  about  110°.     It  is  ob- 
vious, that  in  most  parts  of  the  globe,  the  heat  of  the  atmos- 
}  here  is,  even  in  summer,  less  than  that  of  the  human  body. 
In  our  latitude,  the  mercury  rarely  attains  98°,  and  sometimes 
it  descends  to  several  degrees  below  zero. 

550.  Captain  Parry,  with  his  ship's  company,  in  his  voyage 
of  discovery  to  the  arctic  regions,  wintered  in  a  climate  where 
the   mercury  was  at  40°,  and  sometimes  at  55°  below  zero. 
Captain  Back  found  it  70°  below  zero.     These  were  72°  and 
102°  below  the  freezing  point,  or  about  200°  below  that  of 
their  own  bodies,  and  still  they  were  able  to  resist  this  low 
temperature,  and  escape  being  "  frost-bitten." 

551.  Captain  Lyon,  who  accompanied  Captain  Parry  in  his 
second  voyage  to  the  northern   regions,  found  the  tempera- 
ture of  an  arctic  fox  to  be  106°,  while  that  of  the  atmosphere 
was  32°  below  zero ;  making  a  difference  between  the  tem- 
perature of  the  fox  and  that  of  the  atmosphere,  of  138°.     Cap- 
tain Scoresby  found  the  temperature  of  a  whale,  in  the  Arctic 
Ocean,  to  be  104°,  or  nearly  as  high  as  that  of  other  animals 
of  the  same  kind  in  the  region  of  the  equator,  while  the  tern 
perature  of  the  ice  was  as  low  as  32°,  and  the  water  was 
nearly  as  cold.     These  facts  show  what  a  strong  counteract- 
ing energy  there  is  in  animals  against  the  effects  of  cold. 

552.  On  the  other  hand,  it  has  been  ascertained  by  numer- 
ous and  well-conducted  experiments,  that  the  human  body  can 

549.  What  is  the  temperature  of  the  human  body  ?  Of  birds  ?  PI  oW 
does  the  heat  of  the  atmosphere  in  summer,  in  our  latitude,  compare  vn.  -, 
mat  of  the  human  system  ?  o50.  What  is  related  of  Captain  Parry  ?  Of 
Captain  Back  ?  551.  Of  Captain  Lyon  ?  Of  Captain  Scoresby  ?  What  dc 
*hese  facts  show  ?  5o'2.  What  has  been  ascertained  on  the  other  hand  ? 


%2i>t  ANAiOMY,    PHYSIOLOGY,    AND    HYGIENE. 

be  exposed,  even  for  a  length  of  time,  to  a  very  high  tem- 
perature, without  essentially  elevating  that  of  the  body.  Chan- 
trey,  the  sculptor,  often  entered  the  furnace,  heated  for  drying 
his  moulds,  when  the  temperature  indicated  by  the  thermom- 
eter was  330°.  Chaubert,  the  Fire-King,  is  said  to  have 
entered  ovens  when  heated  to  600°.  In  1774,  Sir  Charles 
Blagden  entered  a  room  in  which  the  mercury  rose  to  260°. 
He  remained  eight  minutes  without  suffering. 

553.  In  order  "to  render  it  certain  that  there  was  no  fallacy, 
says  Sir  Charles  Blagden,  "  in  the  degree  of  heat  shown  by 
the  thermometer,  but  that  the  air  breathed  was  capable  of 
producing  all  the  well-known  effects  of  such  a  heat  on  inan- 
imate matter,  I  put  some  eggs  and  beefsteak  upon  a  tin  frame 
placed  near  the  thermometer,  and   farther  distant  from  the 
cockle  than  from  the  wall  of  the  room.     In  about  twenty  min- 
utes the  eggs  were  taken  out,  roasted  quite  hard  ;  and  in  forty- 
seven  minutes,  the  steak  was  not  only  dressed,  but  almost 
dry." 

554.  If  a  thermometer  be   placed  under  the  tongue  of  a 
healthy  person,  in  all  climates  and  seasons  the  temperature 
will  be  found  nearly  the  same.     Sir  Charles  Blagden,  "  while 
in  the   heated   room,  breathed  on    a    thermometer,  and    the 
mercury  sank  several  degrees  ;  and  when  he  expired  forcibly, 
the  air  felt  cool  as  it  passed  through  the  nostrils,  though  it  was 
scorching  hot  when  it  entered  them  in  inspiration." 

Observation.  Did  not  the  human  body  possess  within  itself 
the  power  of  generating  and  removing  heat,  so  as  to  maintain 
nearly  an  equality  of  temperature,  the  most  fatal  consequences 
would  ensue.  In  northern  latitudes,  especially,  in  severe 
weather  of  winter,  the  blood  would  be  converted  into  a  solid 


What  is  related  of  Chantrey  ?  Of  Chaubert  ?  Of  Sir  Charles  Blagden  ? 
553.  Give  Sir  Charles's  own  statement.  554.  What  is  said  of  the  tem- 
perature of  the  human  tongue  ?  Mention  the  experiment  by  Sir  Charles 
Clagden.  What  would  be  the  effect  if  the  human  system  did  not  main 
tain  an  equality  of  temperature  ? 


ANIMAL    HEAT.  2tKl 

mass  ,  and  on  the  other  hand,  the  fatty  secretion,  when  sub- 
jected to  equatorial  heat,  would  become  fluid,  and  life  would 
be  extinguished. 

555.  To  enable  man,  and  other  warm-blooded  animals,  to 
maintain  this  equilibrium  of  temperature  under  such  extremes 
of   heat  and  cold,  naturally  suggests  two  inquiries:      1st.  By 
what  organs  is  animal  heat  generated  ?     2d.  By  what  means 
is  its  uniformity  maintained  ? 

556.  The  ancients  had  no  well -arranged  theory  on  the  sub- 
ject of  animal  heat.     They  believed   that  the  chief  object  of 
respiration  was  to  cool   the  blood,  and  that  the  heart  was  the 
great  furnace  where   all  the  heat  was  generated.     At  a  later 
period,   Mayow,  from  his  discoveries  respecting  respiration, 
asserted  that  the  object  of  respiration  was  to  produce  heat, 
and  denied  that  the  blood  was  cooled  in  the  lungs. 

557.  When  it  was  discovered  that,  both  in  combustion  and 
respiration,  carbonic  acid  was  produced  and  oxygen  absorbed, 
it  led  Dr.   Black  to  conclude  that  breathing  was  a  kind  of 
combustion  by  which  all  the  heat  of  the  body  was  produced. 
This  theory  was  objected  to,  because,  if  all  the  heat  was  gen- 
erated in  the  lungs,  like  those    parts  of  a  stove  in  contact 
with  the  fuel,  they  would  be  at  a  higher  temperature  than  those 
parts  at  a  distance,  which  was  known  not  to  exist. 

558.  The  next  theory,  and  one  which  received  the  sanction 
of  the  scientific  men  of  Europe,  was  proposed  by  Dr.  Craw- 
ford.     He    agreed  with  Dr.    Black   that  heat  not    only  was 
generated  in  the  lungs,  but  that  the  arterial  blood  had  a  greater 
capacity  for  heat  than  the  venous,  and  that  this  increase  ot 
capacity  takes  place  in  the  lungs.     At  the   moment  heat  is 
generated,  a  portion  of  it,  under  the  name  of  latent  heat,  is 
absorbed    and    conveyed  to  the  different  parts  of  the  body 

ooo.  What  inquiries  are  naturally  suggested  ?  5'56.  What  was  the  theo- 
ry of  the  ancients  ?  What  did  Mayow  assert  at  a  later  period  ?  5o7.  What 
was  the  theory  of  Dr.  Black  ?  The  objection  ?  008.  What  was  the  theory 
of  I>r  Crawford  ? 


2.r»f»  ANATOMY.    PTTYSJOLOGY,    AND    HYGIENE. 

Wherever  arterial  blood  is  converted  into  venous,  tins  Inten. 
heat  is  given  out.  But,  unfortunately  for  this  theory,  Dr.  Davy 
proved  the  capacity  of  both,  for  heat,  to  be  nearly  the  same. 

559.  No  one  can  doubi  that  respiration  and  animal  heat 
are   closely   connected.      Those   animals    whose    respiratory 
apparatus  is  the  most  extended,  have  the  highest  temperature. 
An  example  is  seen  in  birds,  whose   organs  of  respiration 
extend  over  a  large  part  of  the  body,  and  their  temperature 
is  12°  above  man  ;  while  the  respiratory  apparatus  of  cold- 
blooded animals,  as  some  kinds  of  fish,  is  imperfect,  and  only 
a  small  quantity  of  blood   is  subjected,  at  any  time,  to  the 
effects  of  respiration. 

560.  To  understand  the  process  by  which  heat  is  generated 
in  the  human  system  and   in  animals,  it  will  be  necessary  to 
state  :    1st.    That  the  apparent  heat  of  a  body,  as  perceived 
by  the  touch,  or  as  indicated  by  a  thermometer,  is   not  the 
measurement  of  heat  contained  in  the  body,  or  its  capacity 
for  heat. 

Illustration.  If  we  mix  one  pound  of  water,  at  the  tempera- 
ture of  60°,  with  another  pound  at  91°,  the  resulting  tempera- 
ture will  be  exactly  the  medium,  or  75£°.  But,  if  we  mix  a 
pound  of  water  at  60°  with  a  pound  of  quicksilver  at  91°,  the 
resulting  temperature  will  be  only  61°,  because  the  capacity 
of  water  for  heat  is  so  much  greater  than  that  of  quicksilver, 
that  the  heat  which  raised  the  quicksilver  31°  will  raise  the 
water  only  1°. 

561.  2d.  When  the  density  and  the  arrangement  of  the 
atoms  of  a  body  are  changed,  its  capacity  to  hold  heat  in  a 
latent  state  is  altered.     If  it  will  retain   more,  heat  will  be 
absorbed  from  contiguous  and  surround' ng  substances ;  but, 

The  objection  ?  559.  In  what  do  all  the  physiologists  of  the  present  day 
concur  ?  How  is  it  proved  that  respiration  and  animal  heat  are  closely  con- 
nected ?  560.  What  is  said  of  the  apparent  heat  of  bodies  ?  How  is  thi? 
illustrated  ?  561.  What  is  the  effect  when  the  density  and  the  arrange 
ruent  of  the  atoms  of  a  body  are  changed  ? 


AM.MAL    II HAT.  2;VJ 

if  its  capacity  for  caloric  is  lessened,  heat  will  be  set  free  and 
given  out  to  surrounding  bodies. 

Illustrations.  )st.  Ice  and  salt,  (Chi.  of  Sodium,)  when 
mixed,  are  converted  into  a  fluid.  In  this  state  they  will  hold 
more  heat  than  when  solid.  The  heat  necessary  to  produce 
this  change  is  drawn  from  the  surrounding  medium,  which  s 
made  proportionally  colder  by  the  loss  of  caloric  imparted  to 
the  ice  and  salt.  It  is  by  this  chemical  process  that  "  ice- 
cream "  is  made. 

2d.  On  the  other  hand,  mix  water  and  sulphuric  acid,  (oil 
of  vitriol,)  of  the  temperature  of  60°,  and  the  mixture  will 
become  quite  warm,  and  will  freely  impart  its  heat  to  sur 
rounding  and  contiguous  objects. 

562.  The    same    principle    is    exhibited,    when    oxygen 
unites  with  an  inflammable  body,  as  in  the  burning  of  wood, 
coal,  oh,  &c.     In  combustion,  the  oxygen  of  the  atmosphere 
unites  with    carbon  and    hydrogen,  and   carbonic    acid  and 
water  are  produced.     This  process,  according  to  all  the  known 
laws  of  caloric,  is  attended  with  heat.     The  quantity  of  heat 
disengaged    in   combustion   is   always   in    proportion   to   the 
amount  of  carbon  and  hydrogen  consumed  ;  thus  a  piece  of 
wood  weighing  one  pound,  in  burning  slowly,  would  give  out 
the  same  quantity  of  heat  as  a  pound   of  shavings  of  the 
same  wood,  in  burning  rapidly.     Upon  these  principles,  the 
production  of  animal  heat  may  be  understood. 

563.  The   food  contains  carbon   and    hydrogen.      These 
exist  in  the  chyle.     The  old  and  waste  atoms  of  the  body 
'ike wise  contain  the  same  elements.     In  the  lungs  the  oxygen 
and   nitrogen  of  the  inspired  air  are   separated.     It  is  now 
supposed  that  the  oxygen  enters  the  capillary  vessels  of  the 

Give  the  1st  illustration.  The  2d.  562.  What  changes  take  place  when 
oxygen  unites  with  an  inflammable  body  ?  To  what  is  the  quantity  of  heat 
proportionate  in  combustion  ?  Give  an  example.  563.  How  are  carbon 
and  hydrogen  supplied  to  the  system?  How  the  oxygen  ?  Where  doe? 
the  oxygen  mingle  with  the  blood? 
22  * 


2'>8  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

lungs,  and  mingles  with  the  blood,  with  which  it  is  carried  tc 
the  heart  and  thence  to  the  nutrient  capillary  vessels  of  every 
part  of  the  system. 

564.  In  the  capillary  vessels,  the  oxygen  of  the  arterial 
blood  unites  with  the  carbon  and  h}  drogen  which  the  refuse 
materials  contain,  and  carbonic  acid  and  water  are  formed. 
The  combustion  of  carbon  and  hydrogen  in  the  capillaries  of 
every  part  of  the  system,  (the  lungs  not  excepted,)  is  attended 
with  a  disengagement  of  heat,  and  the   carbonic    acid    and 
water  are  returned  to  the  lungs  in  the   dark-colored  blood, 
and  evolved  from  the  system. 

565.  Sir  Benjamin  Brodie    and   some  others  have   main- 
tained, that  the  heat  of  the  system  is  generated  exclusively 
by  the  influence  of  the  brain  and  nerves.     This  theory  is  dis- 
carded by  most  physiologists ;  yet  it  is  true  that  the  nervous 
system   exercises   a  great   influence   over  the  action  of  the 
capillary  vessels  in  the  process  of  nutrition,  secretion,   and 
absorption.      When   these    operations    are    most   active,   the 
change  among  the  pirticles  of  matter  of  which  the  body  is 
composed,  is   then    greatest,  and  the   generation  of  heat  is 
increased  in  a  corresponding  degree. 

566.  The  necessity  of  pure,  red  blood  in  the  production  of 
animal  heat,  is  &hown  when  the  vessels  that  carry  blood  to  a 
limb   are   ligated,  or  tied;    the    part   immediately   becomes 
colder.     The   necessity  of  nervous  influence  is  seen  in  the 
diminished  temperature  of  a  paralytic  limb. 

567.  Our  next  inquiry  is,  By  what  means  is  the  uniformity 
of  temperature  in  the  liody  maintained  ?     As  there  is  a  con- 
stant generation  of  heat   in  the   system,  there  would  be  an 
undue  accumulation,  —  so  much  so  as  to  cause  disagreeable 

564.  Where  does  it  unite  with  the  carbon  and  hydrogen  contained  in  the 
body,  and  how  is  heat  generated  ?  565.  What  was  the  theory  of  Sir  Ben- 
jamin Brodie  ?  Is  this  theory  in  general  discarded  ?  What  is  true  of  this 
theory  ?  066.  How  is  the  necessity  of  pure,  red  blood  and  nervous  action 
slirwn  in  the  production  of  animal  heat? 


ANIMAL    HEAT. 

sensations,  —  if  there  were   no   means  by  which  it  could  be 
evolved  from  the  body,  or  its  production  lessened. 

568.  It  has  been  ascertained  that  the  principal  means  by 
which  the  system  is  kept  at  a  uniform  temperature,  is  the 
immense  evaporation  from  the  skin  and  lungs.  These  mem- 
branes, in  an  ordinary  state,  are  constantly  giving  out  water,' 
which  is  converted  into  vapor,  and  carried  off  by  the  surround- 
ing air.  The  quantity  of  heat  abstracted  from  the  system  to 
«jiFect  this,  depends  on  the  rapidity  of  tl  e  change  of  air,  its 
temperature,  and  the  amount  of  water  it  contains  in  a  stale 
of  vapor.  The  quantity  removed  is  greatest  when  the  air 
is  warm  and  dry,  and  the  change,  or  current,  rapid. 

Observations.  1st.  The  first  discovery  of  the  use  of  free 
evaporation  of  the  perspiration  from  the  skin  in  reducing  the 
heat  of  the  body,  and  the  analogy  subsisting  between  this 
process  and  that  of  the  evaporation  of  water  from  a  rough 
porous  surface,  so  constantly  resorted  to  in  warm  countries, 
us  an  efficacious  means  of  reducing  the  temperature  of  the  air 
in  rooms,  and  of  wine  and  other  drinks,  much  below  that  of 
the  surrounding  atmosphere,  was  made  by  Franklin. 

2d.  In  all  ages  nnd  climes,  it  has  been  observed  that  llit-  in 
creased  temperature  of  the  skin  and  system  in  fevers,  is  a!>u,ed 
as  soon  as  free  perspiration  is  restored.  In  damp,  close  wea.ii- 
er,  as  during  the  sultry  days  of  August,  although  the  tempera- 
ture is  lower,  we  feel  a  disagreeable  sensation  of  heat,  because 
the  saturation  of  the  air  with  moisture  lessens  evaporation,  and 
thus  prevents  the  escape  of  heat  through  the  lungs  and  skin. 

3d.  It  is  on  the  principle  of  the  evaporation  of  fluids,  that 
warm  vinegar  and  water,  applied  to  the  burning,  aching  head, 
cools  it,  and  imparts  to  it  a  comfortable  feeling.  The  same 

.068.  What  are  the  principal  means  by  which  a  uniform  temperature  of  the 
body  is  maintained  ?  On  what  does  the  quantity  of  heat  abstracted  from 
the  system  depend?  What  discovery  relative  to  animal  heat  is  due  to 
Franklin  ?  What  is  said  of  free  perspiration  in  fevers  ?  What  occasions 
the  disagreeable  sensation  of  heat  in  damp,  close  weather  ? 


CGO  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

results  follow  if  warm  liquids  are  applied  to  the  skin  in  the 
hot  stage  of  fever;  and  this  evaporation  can  be  increased  by 
constant  fanning. 

4th.  It  is  frequently  noticed,  in  very  warm  weather,  that 
Jogs  and  other  domestic  animals  are  seen  with  their  tongues 
out  of  their  mouths,  and  covered  with  frothy  secretions.  This 
is  merely  another  mode  of  reducing  animal  heat,  as  the 
skin  of  such  animals  does  not  perspi.e  as  much  as  that  of 
man. 

569.  Under  some  circumstances,  a  portion  of  the  heat  of 
the  system  is  removed  by  radiation.     When  cold  air  comes  in 
contact  with  the  skin  and   mucous  membrane  of  the  lungs, 
heat  is  removed  from  the  body,  as  from  a  stove,  to  restore  an 
equilibrium  of  temperature.     The  removal  of  heat  from  the 
body  is  greatest  when  we  are  in  a  current  of  cold  air,  or 
when  a  brisk,  cold  wind  is  blowing  upon  us. 

570.  As  the  primary  object  of  the  different  processes  of 
nutrition  is  to  supply  animal  heat,  so  the  action  of  the  dif- 
ferent nutritive   organs  is   modified  by   the  demands  of  the 
system  for  heat.     When   heat  is   rapidly  removed  from   the 
body,  the   functional  activity   of  the    organs  of  nutrition    is 
increased.     When  the  system  is  warmed  by  foreign  influence, 
the  activity  of  the  nutritive  organs  is  diminished.     This  leads 
to  the  natural,  and,  we  may  add,  instinctive  change  in  the 
quality  and  quantity  of  food  at  different  seasons  of  the  year. 

569.  When  is  heat  radiated  from  the  body  ?  When  is  it  greatest  f 
570.  What  is  the  primary  object  of  the  different  processes  of  nutrition  ? 
When  is  the  activity  of  the  nutritive  organs  increased  ?  When  diminished  ? 
To  what  does  this  lead  ? 


IIYGiEINE    OF    ANIMAL    IILAT.  261 


CHAPTER    XXVIII. 

HYGIENE     OF     ANIMAL    HEAT. 

571.  THE  amount  of  heat  generated  in  man  and  inferior 
animals  depends   upon  the  quantity  and  quality  of  the  food, 
age,  exercise,  the  amount  and  character  of  the  respired  air, 
condition  of  the  brain,  skin,  and  general  system. 

572.  Animal  heat  is  modified  by  the  proportion  of  digest- 
^ble  carbon  which  the  food  contains,  and  by  the  quantity  con- 
sumed.    As  the  kind  of  fuel  that  contains  the  greatest  amount 
of  combustible  material  evolves  the  most  caloric  when  burned, 
so  those  articles  of  food  that  contain  the  greatest  quantity  of 
carbon   produce  the  most  heat  when  converted    into   blood. 
The     inhabitants    of    the    frigid    zones,    and    individuals  in 
temperate  climates  during    the   cold    season,  consume    with 
impunity   stimulating    animal    food,   that    contains    a   large 
proportion  of   carbon,  while  the  inhabitants  of  the  tropical 
regions,  and  persons  in  temperate  climates  during  the  warm 
season,  are  more  healthy  with  a  less  stimulating  or  vegetable 
diet. 

Observation.  When  we  ride  or  labor  in  cold  weather,  an 
adequate  amount  of  nutritious  food  will  sustain  the  warmth  of 
the  system  better  than  intoxicating  drinks. 

573.  Age  is  another  influence  that  modifies  the  generation 
of  animal  heat.     The  vital  forces  of  the  child  being  feeble, 
less  heat  is  generated  in  its  system  than  in  that  of  an  adult. 

,571 — 585.  Give  the  hygiene  of  animal  heat.  571.  State  some  of  the  influ- 
ences that  modify  the  generation  of  animal  heat.  572.  What  element  of 
the  food  influences  the  generation  of  heat?  When  and  where  can  animal 
food  be  eaten  with  impunity  ?  Give  the  practical  observation. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

The  experiments  of  Dr.  Milne  Edwards  show  that  the  power 
of  producing  heat  in  warm-blooded  animals,  is  at  its  minimum 
at  birth,  and  increases  successively  to  adult  age  ;  and  that 
young  children  part  with  their  heat  more  readily  than  adults, 
and,  instead  of  being  warmer,  are  generally  a  degree  or  two 
colder.  After  adult  age,  as  the  vital  powers  decline,  the 
generation  of  heat  is  diminished,  as  the  energies  of  the  sys- 
tem are  lessened.  Hence  the  young  child,  and  the  debili- 
tated aged  person,  need  more  clothing  than  the  vigorous 
individual  of  middle  age. 

574.  Exercise  is  an  influence,  that  modifies  the  generation 
of  animal  heat.  As  carbon  and  hydrogen  enter  into  the  com- 
position of  the  organs  of  the  body,  whatever  increases  the 
flow  of  blood  in  the  system,  increases  also  the  deposition  of 
new  material,  and  the  removal  of  the  waste  particles.  This 
change  among  the  particles  of  matter  is  attended  with  an 
elevation  of  temperature,  from  the  union  of  oxygen  with  the 
carbon  and  hydrogen  of  the  waste  atoms.  For  this  reason,  a 
person  in  action  is  warmer  than  in  a  quiescent  state.  Conse- 
quently, the  amount  of  clothing  should  be  increased,  when 
exercise  or  labor  is  diminished  or  suspended. 
'  575.  On  the  other  hand,  whatever  impedes  the  circula- 
tion and  the  interchange  of  the  atoms  of  matter,  diminishes 
animal  heat.  Common  observation  shows,  that  the  extremities 
are  not  as  warm  when  tight  gloves  or  boots  are  worn  as 
when  they  are  loose.  One  reason  is,  the  circulation  of  blood 
is  impeded,  which  is  attended  with  less  frequent  change  of  ihe 
particles  of  matter. 

576.  TJie  quantity  of  air  which  is  inhaled  modifies  the  heat 
of  the  system.  In  the  generation  of  heat  in  a  stove,  air, 
or  oxygen,  is  as  essential  as  the  wood  or  coal.  It  is  equally 

What  do  the  experiments  of  l)r.  Milne  Edwards  show  ?  574.  Why 
does  exercise  influence  animal  heat  ?  575.  What  is  the  effect  when  the 
circulation  of  blood  is  impeded  ?  Give  examples.  576.  Why  do  those 
persons  that  have  broad  chests  and  voluminous  lungs  suffer  less  froir 
cold  than  the  narrow-chested  with  small  lungs. 


HYGIENE  OF  ANIMAL  HEAT.  263 

so  m  the  production  of  animal  heat.  The  oxygen  of  the 
inspired  air  should  be  in  proportion  to  the  carbon  and  hydro- 
gen to  be  consumed.  This  requires  voluminous  lungs, 
together  with  free  movements  of  the  ribs  and  diaphragm. 
A  person  whose  chest  is  small,  and  whose  apparel  is  worn 
tight  over  the  ribs,  suffers  more  from  the  cold,  and  complains 
more  frequently  of  chilliness  and  cold  extremities,  than  the 
broad-chested  and  loosely  dressed. 

Observation.  Fishes  that  breathe  by  means  of  gills,  as  the 
cod,  pike,  &c.,  depend  solely  on  the  small  quantity  of  oxygen 
that  is  contained  in  the  air  mixed  with  the  water.  Their 
temperature  is  not  much  greater  than  the  medium  in  which 
they  live.  Whales,  dolphins,  &c.,  breathe  by  means  of  lungs  . 
and  the  inhalation  of  atmospheric  air  makes  their  temperature 
about  100°.  independent  of  the  heat  of  the  element  in  which 
they  live. 

577.  The  quality  of  respired  air  influences  the  generation 
of  animal  heat.     In  vestries,  and  other    public  rooms,  when 
crowded  with  an  audience,  where  the  ventilation  is  inadequate, 
the  lamps  will  emit  but  a  faint  light,  because  the  oxygen  is 
soon  expended,  and  there  is  not  enough  of  the  vivifying  prin- 
ciple to  unite  with  the  oil  and  disengage  light.     In  the  human 
body,  when  the   respired  air  has  lost  some  of  its  life-giving 
properties,  the  combustion  that  takes  place   in  different  parts 
of  the  system  is  not  so  complete  as  when  it  contains  a  proper 
proportion  of   oxygen  ;    and  hence  less  heat  is  disengaged. 
For  this  reason,  those  persons  that  breathe  impure  air,  either 
in  the  daytime  or  night,  require  more  clothing,  than  those 
that  work  and  sleep  in  well- ventilated  rooms. 

578.  The  condition  of  the  brain  and  nervous  system  affects 


What  is  said  of  those  fishes  that  breathe  by  means  of  gills  ?  Of  those 
that  breathe  by  means  of  lungs  ?  577.  Why  do  lamps  give  but  a  faint 
light  in  crowded,  un  ventilated  rooms  ?  What  effect  on  animal  heat  has 
impute  air?  5"8.  Mention  the  effects  of  some  of  the  mental  emotions  ou 
auimal  heat. 


>i  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

the  generation  of  animal  heat.  If  the  brain  is  diseased,  or 
the  mind  is  absorbed  in  thought,  depressed  by  sorrow,  01 
aroused  from  fear,  the  breathing  becomes  slow  and  scarcely 
perceptible,  and  a  chilliness  pervades  the  body,  particularly 
Ihe  extremities ;  while,  on  the  contrary,  if  the  mind  and  ner- 
vous system  are  excited  by  joyous  and  agreeable  emotions, 
the  circulation  of  blood  is  quicker,  and  the  system  more  pow- 
erfully resists  external  cold.  During  sleep,  when  the  brain 
is  partially  inactive,  less  heat  is  generated  than  when  awake. 
Observation.  The  preceding  remark  explains  why  an  indi- 
vidual who  sleeps  in  the  same  clothing  that  was  adequate  tn 
prevent  chills  while  awake,  contracts  a  cold,  unless  he  throws 
over  him  an  additional  covering. 

579.  TJie  state  of  the  skin  exercises  much  influence  in  the 
generation  of  heat.     If  the  functions  of  this   membrane  are 
not  interrupted,  more  heat  will  be  generated  than  when  it  is 
pallid  and   inactive.      The  action  of   the  capillaries  is  most 
energetic  when  the   skin    is  clean ;    on   this  account,  before 
taking  a  walk  or  a  ride,  in  cold  weather,  remove  all  impurities 
from  the  skin,  by  thorough  ablution  and  vigorous  friction. 

580.  The  amount   and  kind  of  clothing  modify  the  tem- 
perature of  the  system.     Those  persons  that  are  well  clothed 
have  greater  power  to  resist  cold  than  the  thinly  apparehea, 
because  both  the  evaporation  and  the  radiation  from  the  skin 
are  impeded,  and  less  heat,  in  consequence,  is  abstracted  from 
the  body.     If  the  articles  of  apparel  possess  the  property  of 
retaining  air  in  their  meshes,  as  flannel,  the  removal  of  heat 
is  not  as  rapid  as  when  linen  is  worn. 

Observation.    In  winter,  although  more  heat  is  generated  in 
the  system  than   in   summer,  yet  we  require   more  clothing, 


What  does  the  preceding  remark  explain?  579.  What  suggestion 
respecting  the  condition  of  the  skin  before  taking  a  walk  or  ride  in  a  cold 
day?  Why?  580.  Do  the  amount  and  kind  of  clothing  affect  anima. 
heat?  What  is  said  of  well-clothed  persons?  When  does  the  system 
generate  the  must  heat } 


HYGIENE  OF  ANIMAL  HEAT. 


and  also  those  articles  that  are  posr  conductors  of  heat,  because 
caloric  is  more  rapidly  extracted  in  clear,  cold  weather,  than 
in  a  warm  day. 

581.  The  health  and  constitution  influence  the  generation 
of  heat.     When  the  health  is  firm,  and  the  constitution  vigor- 
ous, less  clothing  is  needed,  for  the  change  among  the  par- 
ticles of  matter  is  more  rapid,  and   more  heat  is  generated, 
than  when  the  opposite  condition  obtains.     Persons  of  a  fee- 
ble constitution,  particularly,  if  any  of  the  vital  organs*  are 
diseased,  need  more  clothing  and  require  rooms  of  a  warmei 
temperature,  than  individuals  who  are  free  from  disease  and 
have  a  vigorous  constitution. 

Observation.  Persons  who  are  infirm,  and  whose  vital 
powers  are  feeble,  in  general,  accustom  themselves  to  an 
undue  amount  of  clothing  and  warm  rooms.  A  more  judi- 
cious practice  would  be,  to  exercise  more  and  use  a  moderate 
amount  of  clothing,  together  with  a  more  nutritious  diet. 

582.  The  surplus  heat  should  be  removed  equally  from  all 
parts  of  the  system.     The  rapid  evaporation  of  fluids,  as  in 
free  perspiration,  or  from  radiation,  as  in  a  cold  atmosphere, 
is  attended  with  a  removal  of  heat  from  the  system.     This 
modifies  the  action  of  the  circulatory  vessels.     Consequently, 
if  heat  is  suddenly  and  rapidly  abstracted   from   one  part  of 
tne   system,  the  equilibrium  of  the  circulation  is  destroyed, 
which  will  produce  disease. 

Observation.  Currents  of  air  that  impinge  upon  small 
portions  of  the  body,  as  from  small  apertures,  or  from  a 


*  The  brain,  lungs,  heart,  and  digestive  organs,  are  called  vital  organs. 

Why  do  we,  then,  require  more  clothing  in  winter  than  in  summer  ? 
581.  Why  do  persons  of  firm  health  and  vigorous  constitutions  need  less 
clothing  than  those  who  are  feeble  ?  What  is  a  general  practice  among 
infirm  persons?  What  would  be  more  judicious?  582.  Why  should  thu 
surplus  heat  be  removed  equally  from  all  parts  of  the  system  ?  What  ie 
said  respecting  currents  of  air  from  small  apertures  ? 

23 


26t)  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

window  slightly  raised,  should  be  avoided.  They  are  more 
dangerous  than  to  expose  the  whole  person  to  a  brisk  wind, 
because  the  current  of  air  removes  the  heat  from  the  part 
exposed,  which  disturbs  the  circulation  of  blood  and  causes 
disease,  usually  in  the  form  of  "  colds."  For  the  same 
reason,  it  is  not  judicious  to  stand  in  an  open  door,  or  the 
opening  of  a  street. 

583.  The  system  suffers  less  when  the  change  of  tempera- 
lure  is  gradual.     The  change  in  the   production  of  heat,  as 
well  as  in  the  evaporation  of  fluids  from  the  system,  is  gradua) 
when  not  influenced  by  foreign  causes.     This  gradual  change 
is  known  under  the  name   acclimation.     By  this  means  the 
body   is   enabled   to    endure    tropical   heat   and    polar  cold. 
Owing  to  this   gradual  adaptation  of  the  system  to  different 
temperatures,  we  can  bear  a  greater  degree  of  heat  in  the 
summer  between  the  tropics,  than  in  the  winter  under  the 
polar  circles.     On  the  other  hand,  we  can  endure  a  greater 
degree  of  cold   in  winter  and  in  the  arctic  region,  than  in 
the  summer  and  in  equatorial  countries. 

584.  The  sensation  of  heat  which  would  be  oppressive  in 
a  mild,  warm  day  of  January,  would  only  be  grateful  in  July, 
and   a  degree  of  cold  which  could  scarcely  be   endured  in 
August,   would    not    be    uncomfortable    in  December.     The 
changes  of  season  in  our  latitude  prevent  the  disagreeable  and 
perhaps  fatal  consequence  that  would   follow,  if  no  spring  or 
autumn  intervened  between  the  severity  of  winter's  cold  and 
che  intensity  of  summer's  heat.     During  the  transition  periods, 
the  constitution  is  gradually  changed,  and  adapted  to  bear  the 
extremes  of  temperature  without  suffering.     The  amount  of 

583.  In  what  manner  should  change  of  temperature  take  place,  to  be 
adapted  to  the  body  ?  How  is  the  body  enabled  to  endure  tropical  heat 
and  polar  cold  5  State  some  of  the  effects  of  the  gradual  adaptation  of  the 
system  to  different  temperatures.  584.  What  is  said  relative  to  a  warm  day 
in  winter  ?  To  a  cold  day  in  summer  ?  What  is  said  of  the  changes  of 
seasons  in  our  latitude  ?  What  effect  on  the  constitution  during  spring 
and  autumn  ?  What  change  in  the  amount  of  heat  generated  ? 


IIYliliiNE    OF    AiMMAL    HEAT.  2 

heat  generated  in  the  nutrient  capillary  vessels,  is  ^  like  wise 
diminished  or  increased  as  the  temperature  of  the  season 
becomes  greater  or  less. 

585.  But,  on  the  contrary,  we  cannot  suddenly  pass  from 
one  extreme  of  temperature  to  the  other  with  impunity.  Let 
an  inhabitant  of  Quebec  suddenly  arrive  in  Cuba  in  February, 
and  he  would  suffer  from  languor  and  exhaustion ;  after  be- 
coming acclimated  to  this  tropical  climate,  let  him  suddenly 
return  to  Quebec  in  January,  and  the  severity  of  the  weather 
would  be  almost  insupportable. 

Observations.  1st.  Experience  shows  that  heated  rooms,  as 
well  as  tropical  climates,  lessen  the  generation  of  heat  in  the 
body,  and  likewise  the  power  of  resisting  cold.  It  would  be 
idle  for  the  merchant  from  his  warehouse,  or  the  mechanic 
from  his  heated  shop,  to  attempt  to  sit  on  the  box  with  a 
coachman,  with  the  same  amount  of  clothing  as  his  compan- 
ion, who  is  daily  exposed  to  the  inclemency  of  the  weather. 

2d.  "  It  is  the  power  of  endurance  of  cold  at  one  period, 
and  the  absence  of  its  necessity  at  another,  that  enables  ani- 
mals, in  their  wild  and  unprotected  state,  to  bear  the  vicissi- 
tudes of  the  seasons  with  so  little  preparation  in  clothing,  and 
so  little  real  inconvenience." 


585.  What  effect  on  the  system  has  a  sudden  transition  from  a  cold  to  a 
warm  climate  ?  What  does  experience  show  ?  Why  do  wild  animals  beat 
the  vicissitudes  of  the  seasons  with  so  little  preparation  in  clothing  ? 


VH58  ANATOMY,    PHYSJOLOttY,    AMD    HYGIENE. 

'•    ^Jfr_~-' 

CHAPTER     XXIX. 

THE    VOICE. 

* 

586.  THE  beautiful   mechanism  of  the  vocal   instrument, 
which  produces  every  variety  of  sound,  from  a  harsh,  unme- 
lodious  tone,  to  a  soft,  sweet,  flute-like  sound,  has,  as  yet,  been 
imperfectly  imitated  by  art.     It  has  been  compared,  by  many 
physiologists,  to  a  wind,  reed,  and  stringed  instrument.      This 
inimitable,  yet  simple  instrument,  is  the  Lar'ynx. 

587.  Incidentally,  the   different  parts    of  the   respiratory 
organs,  as  well  as  the  larynx,  are  subservient  to  speaking  and 
singing.     The  tongue,  nasal  passages,  muscles  of  the  fauces 
and  face,  are  agents  which  aid  in  the  intonation  of  the  voice. 

ANATOMY  OF  THE  VOCAL  ORGANS. 

588.  The  LARYNX  is  a  kind  of  cartilaginous  tube,  which, 
taken  as  a  whole,  has  the  general  form  of  a  hollow,  reversed 
cone,  with  its  base  upward  toward  the  tongue,  in  the  shape  of 
an  expanded   triangle.      It    opens    into  the    pharynx,  at   its 
superior  extremity,  and  communicates,  by  its  inferior  opening 
with  the  trachea.     It  is  formed  by  the  union  of  five  cartilages, 
namely,  the  Thy'roid,  the  Cri'coid,  the  two  A-ryt-e'noid,  and 
the  Ep-i-glot'tis.     These  are  bound  together  by  ligaments, 
and  moved  by  muscles. 


586.  What  is  said  of  the  structure  of  the  vocal  instrument  ?  With  what 
Instrument  have  physiologists  compared  it  ?  What  is  the  vocal  instrument 
called  ?  587.  What  organs  are  called  into  action  in  speaking  beside  the 
larynx  ?  588 — 596.  Give  the  anatomy  of  the  vocal  organs.  588.  Describe 
the  larynx.  Name  the  cartilages  that  form  the  larynx. 


ANATOMY  OF  THE  VOCAL  ORGANS. 

589.  The   THYROID  CARTILAGE  is 
and   forms  the  prominence  in  the 

Po'mum  A-da'mi,  (Adam's  apple.)  It  is  composed  of  twc 
parts,  and  is  connected  with  the  bone  of  the  tongue  above, 
and  with  the  cricoid  cartilage  below. 

590.  The  CRICOID  CARTILAGE  takes  its  name  from  its  resem- 
blance to  a  ring.     It  is  situated  below  the  thyroid  cartilage  , 
it  is  narrow  in  front,  broader  at  the   sides,  and   still  broader 
behind,  where    it   is   connected   with   the   thyroid    cartilage 
Below,  it  connects  with  the  first  ring  of  the  trachea. 


Fig.  102. 


Fig.  103. 


Fig  102.  A  side  view  of  the  cartilages  of  the  larynx.  *  The  front  side  cf  the  tny 
roid  cartilage.  1,  The  os  hyoides,  (bone  at  the  base  of  the  tongue.)  2,  The  liga- 
ment that  connects  the  hyoid  bone  and  thyroid  cartilage.  3,  4,  5,  The  thyroid  car- 
tilage. 6,  The  cricoid  cartilage.  7,  The  trachea. 

Fig  103.  A  posterior  view  of  the  cartilages  and  ligaments  of  the  larynx.  1,  The 
posterior  face  of  the  epiglottis.  3,  3,  The  os  hyoides.  4,  4,  The  lateral  ligaments 
which  connect  the  os  hyoides  and  thyroid  cartilage.  5,  5,  The  posterior  face  of  the 
thyroid  cartilage.  6,  6,  The  arytenoid  cartilages.  7,  The  cricoid  cartilage.  8,  8, 
The  junction  of  the  cricoid  and  the  arytenoid  cartilages.  12.  The  first  ring  of  the 
irartiea. 


689.  Describe  the  thyroid  cartilage.  590.  From  what  does  the  cricoid 
cartilage  derive  its  name  ?  Where  is  it  situated  ?  Explain  fig.  102. 
Fig.  103. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


591.  The    ARYTENOID   CARTILAGES    are    small    triangular 
bodies  placed  upon    the  back  part  of  the  cricoid   cartilage. 
They  are    connected  with    the    thyroid    cartilages,   by  four 
'igaments,  called  Vo'cal  Cords. 

592.  The  EPIGLOTTIS  is  fibre-cartilaginous,  and  is  placed 
oehind  the  base  of  the  tongue.     In  shape  it  resembles  a  leaf 
of  parsley. 

593.  The  VOCAL  CORDS,  or  ligaments,  are  formed  of  elastic 
and  parallel  fibres,  enclosed  in  a  fold  of  mucous  membrane. 
They  are  about  two  lines  in  width,  and  pass  from  the  anterior 
angle  of  the  thyroid  cartilage,  to  the  two  arytenoid  cartilages. 


Fig.  104. 


Fig.  105. 


Fig.  104.  An  ideal,  lateral  section  of  the  larynx.  1,  1,  The  upper  voca.  cords. 
2,  2,  The  lower  vocal  cords  3,  3,  The  glottis.  4,  4,  The  ventricles  of  the  larynx. 

Fig.  105.  A  vertical  section  of  the  larynx.  2,  The  os  hyoides.  4,  The  apex  of 
the  epiglottis.  7,  The  superior  vocal  ligament.  9,  The  ventricle  of  the  larynx. 
10.  The  lower  vocal  ligament.  11,  The  arytenoid  cartilage.  12,  13,  The  cricoid 
c.-irtilage.  14,  The  trachea.  18,  The  oesophagus. 


591.  Describe  the  arytenoid  cartilages.  692.  What  is  said  of  the  epi- 
glottis? 593.  Give  the  structure  of  the  vocal  cords.  Where  is  the  ventri- 
cle of  the  larynx  ?  Where  is  the  glottis  situated  ?  What  is  represented 
by  fig.  104  ?  Explain  fig.  105. 


ANATOMY  OF  THE  VOCAL  ORGANS.          '21  I 

The  one  is  called  the  superior,  and  the  other*  the  inferior  vocu 
ligament.  The  cavity,  or  depression  between  the  superior 
and  inferior  ligament,  is  called  the  ventricle  of  the  larynx. 
The  aperture,  or  opening  between  these  ligaments,  is  called 
the  glottis ,  or  chink  of  the  glottis.  It  is  about  three  f  jurtiis 
of  an  inch  in  length,  and  one  fourth  of  an  inch  in  width,  the 
opening  being  widest  at  the  posterior  part.  This  opening  is 
enlarged  and  contracted  by  the  agency  of  the  muscles  appro- 
priated to  the  larynx. 

Fig.  106. 


Fig.  106.  A  view  of  the  larynx  from  above,  showing  the  vocal  ligaments.  1,  Tlio 
anterior  edge  of  the  larynx.  4,  The  posterior  face  of  the  thyroid  cartilage.  5,5,  The 
aryterioid  cartilages.  6,  6,  The  vocal  ligaments.  7,  Their  origin,  within  the  angle 
of  the  thyroid  cartilage.  9,  Their  termination,  at  the  base  of  the  arytenoid  cartilages 
e,  10,  The  glottis. 

594.  The  larynx  is  connected  by  muscles  with  the  sternum, 
iBSophagus,  base  of  the  skull,  hyoid  bone,  lower  jaw,  a.:i 
tongue.  This  organ  is  supplied  with  a  large  number  of  blood- 
vessels, and  it  likewise  receives  nerves  from  the  sympathetic 
system,  and  two  large  nerves  from  the  tenth  pair.  The  num- 
ber and  size  of  the  nervous  filaments  distributed  to  the 
mucous  membrane  of  the  larynx,  render  it  more  sensitive 
than  any  other  portion  of  the  respiratory  organs. 

How  is  the  glottis  enlarged  or  contracted  ?  Explain  fig.  106.  594.  By 
what  means  and  to  what  organs  is  the  larynx  connected  ?  Why  is  thfr 
jirynx  more  sensitive  than  other  parts  of  the  respiratory  organs  ? 


272  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

595.  The  larynx  is  much  more  developed  and  prominent 
in  man  than  in  woman.     In  the  former,  the  anterior  angle  of 
the  thyroid  cartilage  is  acute,  while  in  the  latter  it  is  rounded, 
and  the  central  slope  of  the  superior  border  of  the  same  carti- 
lage is  less  deep,  and  the  epiglottis  smaller  and  less  prominent, 
than  in  man. 

596.  The   difference   in   the  formation  of  the   larynx   in 
infancy  is  less  striking ;    but  at  a  later  period,  it    is    more 
developed  in  the  male  than  in  the  female.     It  is  very  remark 
able  that  this  increase  is  not  progressive,  like  that  of  othe 
organs,  but,  on  the  contrary,  develops   itself  at  once  at  tr  j 
period  of  puberty. 


PHYSIOLOGY  OF  THE  VOCAL  ORGANS. 

597.  In   the  formation   of  the   voice,  each   part   already 
described   performs   an   important   office.     The  cricoid  and 
thyroid  cartilages   give  form  and  stability  to  the  larynx ;  the 
aryienoid  cartilages,  by  their  movement,  vary  the  width  of  the 
glottis.     The  epiglottis   is  flexible   and   elastic.     When  it  is 
erect,  the  chink  of  the  glottis  is  open,  as  in  inspiration ;  when 
depressed,  as  in  swallowing  food  and  drink,  it  covers  and 
closes  this  aperture.     It  prevents  the  introduction  of  articles 
of  food  into  the  trachea,  and  probably  modifies  sound  as  it 
issues  from  the  glottis. 

598.  The  muscles  of  the  neck   elevate  and  depress   the 
larynx ;  the  muscles  of  the  larynx  increase  or  diminish  the 
width  of  the  glottis;  at  the  same   time,  the  vocal  cords  are 

595.  "What  difference  between  the  formation  of  the  larynx  of  the  female 
and  that  of  the  male  ?  596.  Does  this  difference  exist  in  childhood  ?  Is 
its  development  progressive  ?  597 — 600.  Give  the  physiology  of  the  vocal 
organs.  597.  Which  cartilages  give  stability  and  form  to  the  larynx  ? 
Which  vary  the  width  of  the  glottis  ?  What  is  the  function  of  the  epi- 
clottis  ?  -598.  What  effect  have  the  muscles  of  the  neck  upon  the  larynx  ? 
I'lio  use  of  the  muscles  of  the  larynx  ? 


PHYSIOLOGY  OF  THE  VOCAL  ORGANS.         273 

relaxed  or  tightened,  while  the  muscles  of  the  face  open  and 
close  the  mouth. 

599.  The  elasticity  of  the  ribs  and  the  contraction  of  the 
abdominal  muscles   diminish  the  cavity  of  the  chest,  arid  the 
air,  in  consequence,  is  pressed  from   the  air-cells   into   the 
bronchial  tubes  and  trachea.     It  then  rushes   by  the   vocal 
cords,  and  causes  a  peculiar  vibration,  which  produces  sound. 

Observations.  1st.  Experiments  have  satisfactorily  shown 
that  the  vocal  cords  are  the  principal  agents  in  the  formation  of 
the  voice.  The  tongue,  which  many  have  supposed  to  be  the 
most  important  organ  in  speaking,  is  not  essential  to  sound. 
In  several  instances  it  has  been  removed,  and  the  persons 
thus  mutilated  could  speak  with  fluency. 

2d.  When  the  vocal  cords  are  ulcerated,  or  inflamed,  how- 
ever slightly,  as  in  sore  throat  produced  by  a  cold,  the  voice 
will  be  changed.  The  loss  of  speech  among  public  speakers 
is  generally  produced  by  a  relaxation  of  the  vocal  ligaments. 
Hence,  bronchitis  is  a  misnomer  for  this  affection. 

600.  Sound  is  varied  by  the  velocity  of  the  expelled  cur- 
rent of  air,  and  the  tension  of  the  vocal  ligaments.     The  size 
of  the  larynx,  the  volume  and  health  of  the  lungs,  the  condi- 
tion of  the  fauces   and    nasal    passages,  the   elevation   and 
depression  of  the   chin,  the    development   and    freedom    of 
action  of  the  muscles  which  are  attached  to  the  larynx,  the 
opening  of  the  mouth,  the  state  of  the   mind,  and   general 
health  of  the  system,  influence  the  modulations  of  sound. 

What  effect  has  the  combined  action  of  these  muscles  ?  599.  How  is 
sound  produced  ?  What  have  experiments  shown  ?  What  effect  has  dis 
ease  of  the  vocal  ligaments  upon  the  voice  ?  600.  How  is  sound  varied s 
Mention  other  conditions  that  contribute  to  the  modulation  of  sound. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


CHAPTER    XXX. 

HYGIENE  OF  THE  VOCAL  ORGANS. 

601.  The   voice   can   be   changed  and  modified   by  habit. 
Sailors,  smiths,  and  others,  who  are  engaged  in  noisy  occupa- 
tions, exert  their  vocal  organs  more  strongly  than  those  of 
more  quiet  pursuits.     This  not  only  affects  the  structure  of 
the  vocal  organs,  but  varies  the  intonation  of  the  voice. 

602.  The  voice  is  strong  in  proportion  to  the  development 
of  the  larynx ,  and  the  capacity  of  the  chest.     Singing  and 
reading  aloud  improve  and  strengthen  the  vocal  organs,  and 
give  a  healthy  expansion  to  the  chest.     The  enunciation  of 
the  elementary  sounds  of  the  English  language,  aids  in  devel- 
oping the  vocal  organs,  as  well  as  preventing  disease  of  the 
throat  and  lungs.     This  exercise  also  conduces  to  the  acqui- 
sition of  musical  sounds. 

603.  The   attitude    affects   the   modulation   of  the  voice. 
When  an  individual  stands  erect,  the  movements  of  the  whole 
respiratory   apparatus   are    most   free    and    effective.      The 
larynx  is  brought  forward  by  the  erect  position  of  the  head 
and  the  elevation  of  the  chin.     The  muscles  of  the  arytenoid 
cartilages  are  then  brought  to  a  proper  relation  for  action,  by 
which  a  tension  of  the  vocal  cords  is  produced,  that  favors 
clear  and  harmonious  enunciation. 

Experiment.  Read  with  the  head  bowed  forward  and  the 
chin  depressed ;  then  read  with  the  head  erect  and  the  chin 
elevated,  and  the  difference  in  the  movement  of  the  vocal 

601 — 616.  Give  the  hygiene  of  the  vocal  organs.  602.  How  may  the  voico 
be  strengthened  ?  603.  What  effect  has  the  erect  attitude  upon  the  mod- 
ulations of  the  voice?  Give  the  experiment. 


HYGIENE  OF  THE  VOCAL  ORGANS.  '«J» 

organs,  together  with    the    difference  in    the  voice,  will    be 
manifest. 

Fig.  107.  Fig.  108. 


Fig.  107.    An  improper  position  ;  but  one  not  unfrequently  §een  in  some  of  oai 
common  schools,  and  in  some  of  our  public  speakers. 

Fig.  108.     The  proper  position  for  reading,  speaking,  and  singing. 

604.  If  an  individual  or  class  read  or  sing  when  sitting, 
let  the  position  represented  by  fig.  109  be  adopted,  and  nol 
the  one  represented  by  fig.  110  ;  for  the  erect  position  in 
sitting  conduces  to  the  free  and  effective  action  of  the  res- 
piratory and  vocal  organs,  and  is  as  important  as  the  erect 
attitude  in  standing. 

604.  What  position  should  be  adopted  when  a  person  reads  or  sings 
when  sitting  ?  Why  ? 


'•770 


iN ATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


605.  The  muscles  of  the  neck  should  not  he  compressed.  If 
the  muscles  of  the  neck  and  larynx  are  compressed  by  a  high 
cravat,  or  other  close  dressing,  not  only  will  the  free  and 
eneigetic  movements  of  these  parts  be  impeded,  but  the  tones 
will  be  feeble  and  ineffective.  Therefore  the  dress  of  the 
neck,  particularly  of  public  speakers  and  singers,  should  be 
loose  and  thin.  For  a  warm  dress  upon  the  neck,  when  the 
vocal  organs  are  in  action,  will  induce  too  great  a  flow  of  blood 
to  these  parts,  which  will  be  attended  by  subsequent  debilitv 

Fig.  109. 


Observations.  1st.  The  loss  of  voice,  (lar-yn-gi'Lis,)  which 
is  prevalent  among  public  speakers,  may  be  ascribed  in  part 
to  the  injudicious  dressing  of  the  neck,  and  improper  position 


in  standing. 


P05.  How  should  public  speakers  dress  their  necks  ?    Why  ?    What 
•»  common  cause  of  the  loss  of  voice  ? 


IIYGIENK    OF    THE    VOCAL    ORGANS. 


277 


2d.  When  individuals  have  been  addressing  an  audience  in 
a  warm  room,  or  engaged  in  singing,  they  should  avoid  all 
impressions  of  a  cold  atmosphere,  unless  adequately  pro- 
tected by  an  extra  garment. 

Fig.  110. 


606.  The  condition  of  the  air  modifies  speaking  and  sing- 
ing. As  pure  air  is  more  elastic  and  resonant  than  impure, 
and  as  easy,  melodious  speaking  or  singing  requires  atmos- 
pheric elasticity,  so  school-rooms  and  singing-halls  should  be 
well  ventilated,  if  we  would  be  entertained  with  soft  intona- 
tions in  reading,  or  sonorous  singing. 

Observation.  The  imperfect  ventilation  of  churches  and 
vestries  is  another  cause  of  laryngitis  among  clergymen, 


Give  2d.  observation.     606.   Why  does  easy  and  melodious  speaking 
require  pure  air  ?     What  is  another  cause  of  'aryngitis  among  clergymen 
24 


278  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

This  affection  is  almost  unknown  among  those  who  speak  ir. 
very  open  rooms,  where  stoves  are  o)t  used. 

607.  T/ie   condition   of  the   nasal  passages   and    throat 
modifies  the  voice.     The  enunciation  of  words   is   rendered 
more  or  less  distinct,  in  proportion  as  the  jaws  are  separated 
in  speaking,  and  the  fauces  and  nasal  passages  are  free  from 
obstruction.     For  these  reasons,  the  scholar  should  be  taught 
to   open  the    mouth   adequately  when   reading,  speaking,  or 
singing,  that  the  sounds  formed  in  the  larynx  and  modified  in 
the  fauces  may  have  an  unobstructed  egress. 

Observations.  1st.  If  the  fauces  are  obstructed  by  enlarged 
tonsils,  (a  condition  by  no  means  uncommon  in  children,) 
they  should  be  removed  by  a  surgical  operation,  which  is  not 
only  effective,  but  safe,  and  attended  with  little  suffering. 
The  tonsils  are  situated  on  each  side  of  the  base  of  the 
tongue,  and,  when  enlarged,  they  obstruct  the  passage  through 
which  the  air  passes  to  and  from  the  lungs,  and  the  respiration 
is  not  only  laborious,  but  distressing. 

2d.  When  the  nasal  passages  are  obstructed,  there  is  a 
peculiar  sound  of  the  voice,  which  is  called  "  talking  through 
the  nose."  This  phenomenon  arises,  not  from  the  expired 
air  passing  through  the  nose,  but  from  its  not  being  able  to 
pass  through  the  nasal  passages. 

608.  TJie  state  of  the  mind  and  health  exerts  an  influence 
upon  the  vocal  organs.     "  The  organs  of  the  voice,  in  common 
with  all  other  parts  of  the  bodily  frame,  require  the  vigor  and 
pliancy  of  muscle,  and  the  elasticity  and  animation  of  mind, 
which  result  from    good    health,  in  order   to    perform  their 
appropriate  functions  with  energy  and  effectr     But  these  indis- 
pensable conditions  to  the  exercise  of  vocal  organs,  are,  in 
the  case  of  most  learners,  very  imperfectly  supplied." 

60".  Does  the  condition  of  the  throat  and  nasal  passages  modify  the  voice  ? 
Name  the  influences  that  produce  clear  enunciation  of  words.  What  is  the 
effect  when  the  nasal  passages  are  obstructed  ?  608.  How  are  the  vocal 
organs  influenced  ?  What  do  they  require  ? 


HYGIENE  OF  THE  VOCAL  ORGANS  279 

609.  "  A  sedentary  mode  of  life,  the  want  of  invigorating 
exercise,  close  and  long-continued  application  of  mind,  and, 
perhaps,  an  impaired  state  of  health,  or  a  feeble  constitution, 
prevent,  in  many  instances,  the  free  and  forcible  use  of  those 
muscles  on  which   voice   is   dependent.     Hence    arises   the 
necessity  of  students  of  elocution  practising  physical  exercises 
adapted  to  promote  general  muscular  vigor,  as  a  means  of 
attaining   energy  in   speaking;  the    power  of  any  class    of 
muscles  being   dependent   on    the    vigor  of  the  whole  sys- 
tem." 

610.  "  Gymnastic  and  calisthenic  exercises  are  invaluable 
aids  to  the  culture  and  development  of  the  voice,  and  should 
be  sedulously  practised  when  opportunity  renders  them  acces- 
sible.    But  even  a  slight  degree  of  physical  exercise,  in  any 
form  adapted  to  the  expansion  of  the  chest  and  to  the  freedom 
and  force  of  the  circulation,  will  serve  to  impart  energy  and 
glow  to  the  muscular  apparatus  of  voice,  and  clearness  to  ils 
sound." 

611.  "There    is,  therefore,  a  great  advantage  in  always 
practising  some  preliminary  muscular  actions,  as  an    imme- 
diate preparation  for  vocal  exercises.     The  art  of  cultivating 
the  voice,  however,  has,  in  addition  to  the  various  forms  of 
corporeal  exercise,  practised  for  the  general  purpose  of  pro 
moting  health,  its  own  specific  prescription  for  securing  the 
vigor  of  the  vocal  organs,  and  modes  of  exercise  adapted  to 
the  training  of  each  class  of  organs  separately." 

612.  The  results  of  such  practice  are  of  indefinite  extent. 
They  are  limited  only  by  the  energy  and  perseverance  of  the 
student,  excepting  perhaps  in  some   instances   of  imperfect 
organization.     A  few  weeks  of  diligent  cultivation  are  usually 
sufficient  to  produce  such  an  effect  on  the  vocal  organs,  that 

609.  Why  are  students  of  elocution  in  general  necessitated  to  practise 
physical  exercise  ?  610.  "What  are  invaluable  aids  in  the  culture  of  the 
voice  ?  611.  What  is  said  of  the  art  of  cultivating  the  voice  ?  612.  Are 
the  results  of  such  practices  limited  r  What  exception  ? 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

persons  who  commence  practice  with  a  feeble  and  ineffective 
utterance,  attain,  in  that  short  period,  the  ful.  command  of 
clear,  forcible,  and  varied  tone. 

613.  Repetition   is   essential   to  distinct   articulation  of 
words.     In  teaching  a  child  to  articulate  a  letter  or  word,  in 
the  first  instance,  make  an  effort  to  induce  a  proper  state  of 
the  vocal  organs  by  which  the  particular  sound  is  produced. 
Repeat  the  letter  or  word  again  and  again,  until  all  the  parts 
of  the  vocal  apparatus  harmonize  in  their  movements  to  pro- 
duce the  given  sound.     This  repetition   is   as  necessary  in 
learning  to  read  as  in  singing. 

Observations.  1st.  There  is  nothing  gained  by  trying  to 
teach  a  child  to  pronounce  the  letters  of  the  alphabet,  before 
the  vocal  organs  are  so  developed  that  distinct  utterance  can 
be  given  to  the  proper  sounds. 

2d.  The  drawling  method  of  talking  to  young  children,  as 
well  as  using  words  that  are  not  found  in  any  written  language, 
(called  child's  talk,)  is  decidedly  wrong.  A  child  will  pro- 
nounce and  understand  the  application  of  a  correct  word  as 
quickly  as  an  incorrect  one. 

614.  No  part  of  the  vocal  organs  is  wanting,  with  those 
individuals  thai  stammer,  or  who  have  an  impediment  in  their 
speech.     Some  parts  may  be  more  developed  than  others,  but 
they  generally  are  but  imperfectly  under  the  control  of  the 
will,  and  assume  an  irregular  and  rapid  movement,  while  other 
parts,  the  motions  of  which  are  essential,  remain  compara 
lively  inactive.     This  can  be  seen  by  comparing  the  move- 
ments  of  the  lips,  tongue,  and  larynx,  while  attempting  to 
speak,  in  a  p3rson  who  stammers,  with  the  movements  of  the 
corresponding  parts,  while  speaking,  in  an  individual  who  has 
no  such  impediment. 

613.  Is  repetition  essential  to  distinct  articulation  ?  What  method  is 
suggested  in  teaching  a  child  to  articulate  letters  or  words  ?  Give  obser- 
vation 1st.  Observation  2d.  614.  Are  the  vocal  organs  wanting  in 
stammerers  .  Why  the  defect  in  their  articulation  of  words  ? 


HYGIENE  OF  THE  VOCAL  ORGANS.          281 

615.  Surgical  operations  and    medical  treatment   are   not 
lighly  advantageous  in  a   majority  of  these   cases.     In  the 

young  and  middle  aged,  this  defect  can  be  remedied  by  patient 
and  judicious  training.  At  first,  only  those  letters  and  words 
should  be  spoken  that  can  be  articulated  with  distinctness. 
Let  there  be  repetition,  until  the  words  can  be  spoken  at  any 
rime  with  readiness.  Then  take  for  a  lesson  other  words, 
more  difficult  to  articulate ;  and  pursue  a  similar  process  of 
training  and  repetition,  until  every  part  of  the  vocal  organs 
can  be  called  into  a  ready  and  harmonious  action  in  giving 
utterance  to  any  word  in  common  use. 

616.  The  method  of  removing  foreign  bodies  from   the 
throat.     It  is  not  necessary  to  ascertain  which   passage  the 
foreign  body  is  in,  for  the  immediate  treatment  ought  in  either 
case  to  be  the  same.     Some  person  should  place  one  hand  on 
the  front  of  the  chest  of  the  sufferer,  and,  with  the  other,  give 
two  or  three    smart  blows   upon   the    back,  allowing  a  few 
seconds  to  intervene  between  them.     This  treatment  will  gen- 
erally be  successful,  and  cause  the  substance  to  be  violently 
thrown  from  the  throat. 

Observation.  If  the  foreign  body  passes  into  the  larynx 
violent  spasmodic  coughing  immediately  succeeds,  which  con- 
tinues until  it  is  removed  or  life  is  extinct.  Such  cases  de- 
mand the  prompt  opening  of  the  trachea  below  the  larynx  bv 
a  skilful  surgeon. 

615.  How  can  stammering  be  remedied  ?    616.  "What  is  the  method  o< 
removing  foreign  bodies  from  the  throat  ? 

24* 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


CHAPTER     XXXI. 

0 

THE    SKIN. 

617.  THE  skin  is  a  membrane  which  envelops  the  muscles 
and  other  parts  of  the  system.     In  youth,  and  in  females  par- 
ticularly, it  is  smooth,  soft,  and  elastic.     In  middle  age,  and 
in  males,  it  is  firm  and  rough  to  the  touch.     In  old  age,  in 
persons  who  are  emaciated,  and  about  the  flexions  of  the  joints, 
it  is  thrown  into  folds.     The    interior  of  the  body,  like  the 
exterior,  is  covered  by  a  skin,  which,  from   the   constantly 
moistened  state  of  its  surface,  is  called  the  mucous   mem- 
brane.    At  the  various  orifices  of  the  body,  the  exterior  skin 
is  continuous  with  the  internal. 

ANATOMY  OF   THE   SKIN. 

618.  The  SKIN,  to  the  naked  eye,  appears  composed  of  one 
membrane.     But  examination  has  shown  that  it  consists  of 
two  layers  of  membrane,  namely,  the  Cu'ti-de,  (scarf-skin,) 
and  the  Cu'tis   Ve'ra,  (true  skin.)     These   layers  are  widely 
different  from  each  other  in  structure,  and  perform  very  di* 
ferem  offices  in  the  animal  economy. 

619.  The  CUTICLE   (sometimes  called  the  ep-i-derm'is)  is 
the  external  layer  of  the  skin.     This  membrane  is  thin  and 

617.  What  is  the  skin  ?  Mention  its  different  appearances  in  its  differ- 
ent conditions  in  the  human  frame.  Is  the  interior  of  the  body,  as  well 
as  the  exterior,  covered  by  a  skin  ?  What  is  the  interior  membrane  called  ? 
Why  has  it  received  this  name  ?  618 — 636.  Give  the  anatomy  of  the  skin. 
618.  What  is  said  of  the  skin  ?  What  is  said  relative  to  these  layers 
of  membrane  ?  619.  Describe  the  cuticle.  What  name  is  sometimes 
applied  to  the  cuticle  ? 


ANATOMY    OF    THE    SKIN.  283 

semi-transparent,  and  resembles  a  thin  shaving  of  soft,  clear 
horn,  and  bears  the  same  relation  to  other  parts  of  the  skin 
that  the  rough  bark  of  a  tree  does  to  the  liber,  or  living  bark. 
The  cuticle  has  no  perceptible  nerves  or  blood-vessels  ;  con- 
sequently, if  it  is  cut  or  abraded,  no  pain  will  be  felt,  and  no 
fluid  will  ooze  from  it.  m 

Experiment.  Pass  a  pin  through  the  portion  of  the  cuti- 
cle that  skirts  the  nails,  or  remove  a  thin  shaving  from  the 
palm  of  the  hand,  and  no  painful  sensation  will  be  expe- 
rienced unless  the  pin  or  knife  penetrates  deeper  than  the 
suticle.  v 

620.  This  membrane  varies  in  thickness  on  different  parts 
of  the  body,  —  from  the  thin,  delicate  skin  upon  the  internal 
flexions  of  the  joints,  to  the  thickened  covering  of  the  soles 
of  the  feet.      The  greater    thickness  of  the    cuticle  of  the 
palms  of  the  hands  and   soles  of  the  feet,  is  manifestly  the 
intentional   work   of    the  Creator ;    for   it    is    perceptible   in 
infants,  even  at  birth,  before  exercise  can  have  had  any  influ- 
ence. 

621.  The  CUTIS  VERA  (sometimes  called   the  co'ri-on)  is 
composed  of   minute  fibres,  which  are  collected   into  small 
bundles  or  strands.     These  are  interwoven  with  each  other 
so  as  to  constitute  a  firm,  strong,  and  flexible  web.     In  the 
superficial  part  of  the  true  skin,  the  web  is  so  close  as  to  have 
the   appearance  of  felt-cloth ;    but  more  deeply,   the    pores 
become  progressively  larger,  and,  upon  the   lower  surface, 
have  a  diameter  of  about  a  line,  or  one  twelfth  of  an  inch. 
This  gives  the  under  surface  the  appearance  of  a  coarse  web. 
The  strands  of  the  under  surface  of  the  true  skin  are  con- 
nected with  the  fibrous  web,  in  which  the  sub-cutaneous  fat 
of    the    body  is    deposited;    while   the   upper  surface    gives 

Give  the  experiment.  620.  What  is  said  of  the  thickness  of  the  cuticle 
in  different  parts  of  the  body  ?  621.  Describe  the  cutis  vera.  By  what 
name  is  .it  sometimes  called  ?  What  is  the  appearance  of  the  upper  sur- 
face of  the  cutis  vera  ?  Of  the  under  surface  ? 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

support  to  the  sensitive,  or  papillary  layer,  which  is  bedded 
a  pon  it. 

Observation.  When  the  skins  of  animals  are  immersed  in 
a  strong  solution  of  oak  or  hemlock  bark,  a  chemical  union 
takes  place  between  the  gelatin,  of  which  the  true  skin  is 
mostly  composed,  and  the  tannin  of  the  bark.  By  this  process 
leather  is  formed,  and  its  peculiar  markings  are  owing  to  the 
papillary  layer. 

Fig.  111. 


Fig.  111.  An  ideal  representation  of  the  papillze.  1,  1,  The  cutis  vera.  2,  2,  The 
papillary  layer.  3,  3,  The  arteries  of  the  papillae  4,  4,  The  veins  of  the  papilla. 
5,  5,  The  nerves  of  the  papillee. 

622.  The  sensitive  layer  of  the  skin  is  thin,  soft,  uneven > 
pinkish  in  hue,  and  composed  of  blood-vessels,  which  confer 
its  various  tints  of  red  ;  and  of  nerves,  which  give  it  the  facul- 
ty of  sensation.     The  unevenness  of  this  layer  is  produced 
by  small,  elongated,  conical  prominences,  called  Pa-pil'l<z. 

623.  Each  PAPILLA  is  composed  of  a  minute  artery,  vein, 
and  nerve.     Some  of  the  prominences  are  arranged  in  conceri- 

How  is  leather  formed  ?  622.  What  is  the  appearance  of  the  sensitive 
layer?  "What  causes  the  unevenness  of  this  layer?  Explain  fig.  11L 
623.  Describe  the  papillae. 


ANATOMY    OF    THE    SKIN.  285 

tiic  ovals,  as  may  be  seen  on  the  ends  of  the  fingers;  others 
are  more  or  less  parallel,  and  pursue  a  serpentine  course  ; 
some  suddenly  diverge,  and  again  reunite,  as  may  be  seen  in 
>he  palm  of  the  hand.  Papillae  are  found  in  every  part  of  the 
skin.  Consequently,  their  number  is  very  great. 

624.  The  cutis  vera  contains  not  only  Arteries,  Veins,  and 
Nerves  but  Lymphatics,  Oil- Glands  and  Tubes,  and  Perspi- 
ratory Glands  and  Tubes. 

,  Fig.  112. 


Fig.  112.  The  arteries  and  veins  of  a  section  of  the  skin.  A,  A,  Arterial  branches. 
B,  B,  Capillary,  or  hair-like  vessels,  in  which  the  large  branches  terminate.  C,  The 
venous  trunk,  collecting  the  blood  from  the  capillaries. 

625.  The  ARTERIES  and  VEINS  of  the  skin  are  very  numer- 
ous. The  larger  branches  of  the  arteries  pass  through  the 
open  meshes  of  the  true  skin,  and  are  subdivided  into  a 
myriad  of  minute  capillary  vessels,  which  form  a  beautiful 
net-work  on  the  upper  surface  of  the  true  skin.  This  vascu- 
lar net  sends  a  branch  to  each  of  the  papillae,  which  opens 
into  and  terminates  in  a  minute  vein.  The  capillary  veins  are 


624.  What  vessels    are  found    in  the   cutis    vera?     Explain  fig.    112. 
625.  "What  is  said  of  the  cutaneous  arteries  ?     Of  the  cutaneous  veins  ? 


286  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

as  numerous  as  the  arteries  which  they  accompany.  They 
unite  and  form  larger  trunks,  as  small  springs  from  the  hill 
side  coalesce  to  form  rivulets. 

626.  The  NERVES  that  are  spread  over  every  part  of  the 
sensitive  layer  of  the  true  skin,  proceed  from  the  spinal  cord. 
As  a  proof  of  the  great  number  of  nervous  filaments  in  the 
skin,  no   part  of  this    tissue  can  be   punctured  with   a  fine 
needle  without  transfixing  a  nerve,  and   inducing  pain.     In 
some   parts  of   the    system,  however,  the  nerves  are  more 
abundant  than  in  others  ;  where  the  sense  of  feeling  is  most 
acute,  we  find  the  greatest  number  of  nerves,  and  those  of  the 
largest  size.     Those  parts  that  are  most  exposed  to  injury  are 
most  sensitive. 

Examples.  1st.  The  conjunctiva,  or  skin  of  the  eye,  is 
pained  by  the  presence  of  a  particle  of  dust,  because  it 
would  render  vision  imperfect. 

2d.  The  lungs,  also,  would  be  injured  by  the  smallest  par- 
ticle of  matter ;  they  are  therefore  protected  by  the  exquisite 
sensitiveness  of  the  lining  membrane  of  the  trachea,  so  that 
a  particle  of  food  or  dust  is  ejected  by  a  convulsive  cough 
before  it  reaches  the  lungs. 

627.  The  nerves  are  more  numerous  in  the   upper  than 
lower  extremities ;  in  greater  numbers  upon  the  palm  than 
the  back  of  the  hand.     They  are,  likewise,  more  abundant 
and  larger  at  the  extremities  of  the  fingers,  and  in  the  lips, 
than  in  any  other  part  of  the  skin. 

Observation.  The  proboscis  of  the  elephant,  the  extremities 
of  the  tails  of  certain  species  of  monkeys,  and  the  tentacula 
of  some  kinds  of  fish,  receive  a  more  abundant  supply  of  sen- 
sitive nerves  than  other  parts  of  their  systems. 


626.  Where  do  the  nerves  of  the  skin  proceed  from  ?  Are  they  numer- 
ous in  this  membrane  ?  How  is  it  proved  ?  "What  is  said  of  those  parts 
most  exposed  to  injury  ?  Give  example  1st.  Example  2d.  627.  Mention 
the  difference  in  the  distribution  of  the  nerves  in  various  parts  of  thr 
body.  Is  this  difference  found  in  the  lower  order  of  animals  ? 


-ANATOMY    OF    THE    SKIN.  287 

628.  In  the  small  papillae,  the  nerve  forms  a  single  loop, 
while  in  papillae  of  larger  size,  and  endowed  with  a  uower 
of  more  exalted  sensation,  the  nerve  is  bent  several  times 
upon  itself  previous  to  completing  the  loop.  These  tittle 
loops  spring  from  a  net- work  of  nerves,  imbedded  in  the 
upper  porous  layer  of  the  true  skin,  at  the  base  of  the  papil- 
he.  This  net-work  of  nerves  receives  its  influence  through 
nerves  which  take  their  winding  course  through  the  fat  dis- 
tended openings  of  the  deeper  layers  of  the  true  skin. 

Fig.  113. 


Fig.  113.  1,  1,  The  cuticle.  2,  2,  The  colored  layer  of  the  cuticle.  3,  3,  Tiie 
papillajy  layer,  exhibiting  the  nerves  as  they  form  loops.  4,  4,  The  net-work  of 
nerves.  5,  5,  The  true  skin.  6,  6,  6,  Three  nerves  that  divide  to  form  the  net- 
work (4,  4.)  7,  7,  7,  The  furrows  between  the  papillae.  8,  8,  8,  Three  papilla: 
magnified  fifty  diameters. 

629.  The  LYMPHATICS  are  found  in  great  numbers  in  the 
true  skin,  and  they  are  so  minute  that  they  cannot  be  seen  with 
the  naked  eye  ;  but  when  these  hair-like  vessels  are  injected 
with  quicksilver,  (a  work  of  great  difficulty,)  the  surface  injected 

628.  How  are  the  nerves  of  the  small  papillae  arranged?  How  in  the 
large  papillae  ?  What  does  fig.  113  represent  ?  629.  What  is  said  of  the 
cutaneous  lymphatics  ?  How  is  their  existence  proved  ? 


288  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

resembles  a  sheet  of  silver.  In  this  way  their  existence  can 
be  imperfectly  demonstrated.  They  are  a  part  of  the  vascu- 
lar net-work  situated  upon  the  upper  surface  of  the  true  skin. 
Each  papilla  is  supplied  with  a  lymphatic  filament,  the  mouth 
of  which  opens  beneath,  and  lies  in  contact  with  the  under 
surface  of  the  cuticle.  This  net-work  of  vessels  communi- 
cates through  the  open  meshes  of  the  true  skin  with  larger 
lymphatic  trunks,  that  open  into  the  venous  svstem. 

Fig.  114. 


Fig.  114.    A  plexus  of  lymphatic  vessels  in  the  skin,  considerably  magnified  from 
an  injected  preparation. 

630.  The  OIL-GLANDS  are  small  bodies  imbedded  in  the 
true  skin.  They  connect  with  the  surface  of  the  skin  by  small 
tubes,  which  traverse  the  cuticle.  In  some  parts,  these  glands 
are  wanting ;  in  others,  where  their  office  is  most  needful, 
they  are  abundant,  as  on  the  face  and  nose,  the  head,  the 
ears,  &c.  In  some  parts,  these  tubes  are  spiral ;  in  others, 
straight.  These  glands  offer  every  shade  of  complexity,  from 
he  simple,  straight  tube,  to  a  tube  divided  into  numberless 


v.  *  what  are  they  a  part  ?  630.  Describe  the  oil-glands.  With  wuat  do 
the)'  connect?  Do  they  exist  in  every  part  of  the  body?  Of  what  form 
arc  tueir  tubes  r 


ANATOMY    OF    THE    SKIN. 


2S9 


ramifications,  and  constituting  a  little  rounded  tree-like  mass, 
about  the  size  of  a  millet  seed. 

631.  In  a  few  situations,  these  small  glands  are  worthy  of 
particular  notice,  as  in  the  eyelids,  where  they  possess  great 
elegance  of  distribution  and  form,  and  open  by  minute  pores 
along  the  lids ;  in  the  ear-passages,  where  they  produce  that 
amber-colored  substance,  known  as  the  ce-ru'men,  (wax  of  the 
ears,)  and  in  the  scalp,  where  they  resemble  small  clusters  of 
grapes,  and  open  in  pairs  into  the  sheath  of  the  hair,  supply- 
ing it  with  a  pomatum  of  Nature's  own  preparing.  The  oil- 
tubes  are  sometimes  called  the  se-ba'ceousfol'li-cles. 

Fig.  115. 


Fig.  115.     1,  An  oil-tube  and  gland  from  the  scalp.     A,  The  gland.    B,  The  tuuo 
slightly  twisted. 

2.  An  oil-tube  and  gtand  from  the  skin  of  the  nose.     The  gland  (A)  is  double,  and 
communicates  with  the  main  tube  (B)  by  means  of  two  smaller  tubes. 

3.  Another  oil-tube  and  gland  from  the   nose.     A,  The  gland.    B,  The  tube  filled 
with  the  peculiar  animalculae  of   the  oily  substances.      Their   heads  are  directed 
inward. 

4.  A  small  hair  from  the  scalp,  with  its  oil-glands.    The  glands  (A)  form  a  duster 
around  the  shaft  of  the  hair-tube,  (C.)     These   ducts  open  into  the  sheath  of  tha 
hair,  (B.)     All  the  figures,  from  1  to  4,  are  magnified  thirty-eight  diameters 

631.  What  is  said  of  these  tubes  in  the  eyelids  ?     In  the  ear  ?     In  the 

scalp  ?     What  are  these  glituds  sometimes  called  ? 

25 


290  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

Observation.  Among  the  inhabitants  of  cities,  and  espe 
cially  in  persons  who  have  a  torpid  state  of  the  skin,  the  con 
tents  of  the  oil-tubes  become  too  dense  and  dry  to  escape  in 
the  usual  manner.  Thus  it  collects,  distends  the  tube,  and 
remains  until  removed  by  art.  When  this  impacted  matter 
reaches  the  surface,  dust  and  smoke  mix  with  it,  then  it  is 
recognized  by  small,  round,  dark  spots.  These  are  seen  on 
the  forehead,  nose,  and  other  parts  of  the  face.  When  this 
matter  is  pressed  out,  the  tube  gives  it  a  cylindrical  form. 
The  parts  around  the  distended  tubes  sometimes  inflame.  This 
constitutes  the  disease  called,  " ac'ne punc-ta'ta" 

632.  The  PERSPIRATORY   APPARATUS   consists    of    minute 
cylindrical  tubes,  which  pass  inward  through  the  cuticle,  and 
terminate  in  the  deeper  meshes  of  the  cutis  vera.     In  their 
course,  each  Httle  tube  forms  a  beautiful  spiral  coil ;  and,  on 
arriving  at   its  destination,  coils  upon  itself    in  such  a  way 
as  to  constitute  an  oval-shaped,  or  globular   ball,  called  the 
perspiratory  gland. 

633.  The  opening  of  the  perspiratory  tube  on  the  surface 
of  the  cuticle,  namely,  "  the  pores,"  is  also  deserving  of  atten- 
tion.    In  consequence  of  its  extremity  being  a  section  of  a 
spirally-twisted  tube,  the  aperture  is  oblique  in  direction,  and 
possesses  all  the  advantages  of  a  valvular  opening,  preventing 
the  ingress  of  foreign  injurious  substances  to  the  interior  of  the 
tube  and  gland. 

634.  "  To  arrive  at  something  like  an  estimate  of  the  value 
of  the  perspiratory  system,  in  relation  to  the  rest  of  the  organ- 
ism, I  counted  the  perspiratory  pores  on  the  palm  of  the  hand, 
and  found  3528  in  a  square  inch.     Now  each  of  these  pores 
being  the  aperture  of  a  little  tube  about  a  quarter  of  an  inch 

What  is  said  of  the  retention  of  the  unctuous  matter  in  the  oil-tubes  ? 
632.  Of  what  does  the  perspiratory  apparatus  consist?  633.  What  is 
peculiar  in  the  opening  of  the  perspiratory  tubes  on  the  surface  of  the  cuti- 
cle ?  634.  How  many  perspiratory  pores  did  Dr.  Wilson  count  upon  a 
square  inch  of  skin  on  the  palm  of  the  hand  ? 


.NATOMY    OF    THE    SKlIi. 


Z!M 


Fig  116  A  perspiratory  gla*d  from  the  palm  of  the  hand,  magnified  forty  diami> 
*.rs.  1,  1,  A  twisted  tube  composing  the  gland.  2,  2,  The  two  excretory  ducis 
from  the  gland.  These  unite  to  form  one  spiral  tube,  that  perforates  the  cuticle,  (UT) 
and  opens  obliquely  on  its  surface  at  4.  The  gland  is  imbedded  in  cells  filled  with 
*at,  which  are  seen  at  5,  5. 


What  does  fig.  116  represent  ? 


'<..)£  ANATOMY,    PHYSIOLOGY,    AiNl>    J'YJIENE. 

long,  it  follows,  that  in  a  square  inch  of  skin  on  the  palm 
of  the  hand  there  exists  a  length  of  tube  equal  to  882  inches, 
or  73£  feet.  Surely  such  an  amount  of  drainage  as  seventy- 
three  feet  in  every  square  inch  of  skin  —  assuming  this  to  be 
the  average  for  the  whole  body  —  is  something  wonderful 
and  the  thought  naturally  intrudes  itself,  What  if  this  drainage 
6e  obstructed  ? 

635.  "  Could  we  need  a  stronger  argument  for  enforcing 
the  necessity  of  attention  to  the  skin  ?     On  the  pulps  of  the 
fingers,  where  the  ridges  of  the  sensitive   layer  of  the  true 
skin  are   somewhat  finer  than  in  the  palm  of  the  hand,  the 
number  of  pores  on  a  square  inch  a  little  exceeded  that  of  the 
palm  ;  and  on  the  heels,  where  the  ridges  are  coarser,  the 
number   of   pores  on   the   square    inch  was  2268,  and   the 
length  of  the  tube  567  inches,  47£  feet. 

636.  "  To  obtain  an  estimate  of  the   length  of  tube  of  the 
perspiratory  system  of  the  whole  surface  of  the  body,  I  think 
that  2800  might  be  taken  as  a  fair  average  of  the  number  of 
pores  in  the  square  inch  ;  and  consequently,  700,  the  number 
of  inches  in  length.     Now,  the  number  of  square  inches  of 
surface  in  a  man  of  ordinary  height  and   bulk  is  2500  ;  the 
number  of  pores,  therefore,  7,000,000  ;  and  the  number  of 
inches  of  perspiratory  tube  is  1,750,000  ;  that  is,  145,833  feet, 
or  48,611  yards,  or  nearly  TWENTY-EIGHT  miles  /" —  Wilson. 

Give  other  computations  in  this  paragraph.  635.  What  is  said  of  the 
number  of  these  }>ores  on  the  pulp  of  the  fing-.rs  ?  On  the  heels  ? 
S36.  What  is  an  average  numbei  of  pores  and  lengtt  tt  tube  of  the  whole 
surface  of  the  body  ?  Give  the  summary  of  th?  .uurocr  vt  pores,  and  num- 
ber of  inches  of  perspiratory  tube. 


PHYSIOLOGY  OF  THE  SKIN.  293 


CHAPTER    XXXII. 

PHYSIOLOGY    OF    THE    SKIN. 

637.  THE  skin  invests  the  whole  of  the  external  surface  of 
the  body,  following  all  its  prominences  and  curves,  and  gives 
protection  to  all  the  organs  it  encloses,  while  each  of  its  sev- 
eral parts  has  a  distinct  use. 

638.  The  cuticle  is  insensible,  and  serves  as  a  sheath  of 
protection  to    the  highly  sensitive   skin  (cutis  veru)  situated 
beneath  it.     The   latter  feels  ;  but  the  former  blunts  the  im- 
pression which   occasions    feeling.     In   some   situations,  the 
cuticle  is  so  dense  and  thick,  as  wholly  to  exclude  ordinary 
impressions.     Of  this  we  see  an  example  in  the  ends  of  the 
fingers,  where  the  hard  and  dense  nail  is  the  cuticle  modified 
for  the  purpose  referred  to.     Were  the  nervous  tissue  of  the 
true  skin  not  thus  protected,  every  sensation  would  be  so  acute 
as  to  be  unpleasant,  and  contact  with  external  bodies  would 
cause  pain. 

639.  The  cuticle,  also,  prevents  disease,  by  impeding  the 
evaporation  of  the  fluids  of  the  true  skin,  and  the  absorption  of 
the  poisonous  vapors,  which  necessarily  attend  various  employ- 
ments.     It,  however,  affords   protection    to  the  system  only 
\vh3n   unbroken,   and   then,    to   the    greatest    degree,    when 
covered  with  a  proper  amount  of  oily  secretion  from  the  oil- 
glands. 

640.  The  cuticle  is,  originally,  a  transparent  fluid,  exuded 

637— 606.  Give  the  physiology  of  the  skin.  637.  What  is  said  of  the 
skin?  638.  Give  a  function  of  the  cuticle.  Does  it  vary  in  thickness  on 
different  parts  of  the  body  ?  Give  examples.  639.  Mention  anothei  use 
of  the  cuticle.  640.  What  is  the  cuticle  originally  ? 

25* 


294  ANATOMY,    PHYSIOLOGY,  AND    HYGIENE. 

by  the  blood-vessels,  and  distributed  as  a  thin  layer  on  the  sur- 
face of  the  true  skin.  While  successive  layers  are  formed  on 
the  exterior  of  the  true  skin,  the  external  cuticular  layers  are 
converted  into  dry,  flattened  scales,  by  the  evaporation  of  their 
fluid  contents.  The  thickness  of  the  cuticle  is  formed  mainly 
from  these  scales. 

641.  The  cuticle  is,  therefore,  undergoing  a  constant  pro- 
cess of  formation  and  growth  at  its  under  part,  to  compensate 
for  the  wear  that  is  taking  place  continually  on  its  surface.     A 
proper  thickness  of  the  cuticle  is  in  this  manner  preserved 
the  faculty  of  sensation  and  that  of  touch  are  properly  regu 
lated  ;  the  places  of  the  little  scales,  which  are  continually 
falling  off  under  the  united  influence  of  friction  and  ablu- 
tion, are  supplied  ;  and  an  action    necessary,  not  merely  to 
the  health   of  the   skin,  but   to   that   of  the    entire  body,  is 
established. 

642.  Whenever   the  cuticle  is  exposed    to  moderate   and 
repeated  friction,  it  becomes  thicker  and  tougher,  as  may  be 
seen  in  the  cuticle  of  the  lady's  finger  that  plies  the  needle 
arid  in  the  hard  or  callous  appearance  of  the  hands  of  farmers 
masons,  and  other  mechanics.     This  enables  them  to  handle 
the  utensils  and  materials  used  in  their  vocations  without  pain 
or  inconvenience. 

Observations.  1st.  When  the  joints  of  the  feet  are  sub- 
jected to  moderate  and  continued  pressure  or  friction,  fre- 
quently one  or  more  of  the  papillae  enlarge.  This  is 
accompanied  with  a  thickening  of  the  layers  of  the  cuticle, 
which  is  termed  a  "  callosity,"  or  "  corn."  These  thickened 
layers  of  the  cuticle  are  broad  at  the  top  and  narrow  at  the 
bottom,  and  the  enlarged  mass  is  conical,  with  the  point 

How  is  the  thickness  of  the  cuticle  mainly  formed  ?  641.  Describe  the 
changes  of  this  membrane.  Show  the  necessity  of  this  constant  growth. 
642.  How  does  moderate  and  repeated  friction  affect  the  cuticle  ?  Give 
examples.  What  is  the  benefit  derived  from  having  the  cuticle  thus 
changed?  What  is  the  result  if  the  joints  of  the  feet  are  subjected  to 
moderate  and  continued  pressure  ?  What  is  the  form  of  a  "  corn  "  ? 


PHYSIOLOGY    OF    THE    SKIN.  295 

innermost.     When  pressedmpon  by  a  tight  shoe,  these  sensitive- 
pa  pi  USB  cause  pain. 

2cl.  To  remove  these  painful  excrescences,  take  a  thick 
piece  of  soft  leather,  somewhat  larger  than  the  corn ;  in  the 
centre  punch  a  hole  of  the  size  of  the  summit  of  the  corn, 
spread  the  leather  with  adhesive  plaster,  and  apply  it  around 
the  corn.  The  hole  in  the  leather  may  be  filled  with  a  paste 
made  of  soda  and  soap,  on  going  to  bed.  In  the  morning, 
remove  it,  and  wash  with  warm  water.  Repeat  this  for 
several  successive  nights,  and  the  corn  will  be  removed.  The 
only  precaution  is,  not  to  repeat  the  application  so  as  to 
cause  pain. 

643.  Let  a  person  unaccustomed  to  manual  labor,  trundle 
the  hand-cart,  or  row  a  boat,  for  several  successive  hours,  and 
.he  cuticle  upon  the  palms  of  the  hands,  instead  of  becom- 
ing thicker  by  use,  is  frequently  separated  from  the  subjacent 
tissues,  by  an  effusion  of  serum,  (water,)  thrown   out  by  the 
vessels  of  the  true  skin.     Had  the  friction  been   moderate, 
And    applied   at   regular   intervals,  instead   of  blisters   being 
formed  upon  the   inside  of  the   hands,  material   would  have 
been  thrown  out  to  form  new  layers  upon  the  lower  surface 
of  the  cuticle. 

644.  The  cuticle  is  interesting  to  us  in  another  point  of 
view,  as  being  the  seat  of  the  color  of  the  skin.     The  differ- 
ence of  color  between  the  blonde  and  the  brunette,  the  Euro- 
pean and  the  African,  lies  in  the  cuticle  ;  —  in  the  deeper,  and 
softer,  and  newly-formed   layers   of  that   structure.     In  the 
whitest  skin,  the  cells  of  the  cuticle  always  contain  more  or 
less  of  a  peculiar  pigment,  incorporated  with  the  elementary 
granules  which  enter  into  their  composition.     In  the  white 

How  can  they  be  removed  ?  What  precaution  is  given  ?  643.  Explain 
why  those  persons  unaccustomed  to  labor,  blister  their  hands  in  rowing  a 
boat  or  performing  ordinary  manual  employment  for  several  successive 
hours.  6-1-t.  In  what  other  point  of  view  is  the  cuticle  interesting  ?  In 
v/hat  nart  of  it  do  we  find  the  coloring  matter  ? 


XJ'M)  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

races,  the  pigmentary  tint  is  extremely  slight,  and  less  in 
winter  than  in  the  summer  season.  In  the  darker  races,  on 
the  contrary,  it  is  deep  and  strongly  marked. 

645.  The  various  tints  of  color  exhibited  by  mankind,  are, 
therefore,  referable  to  the  amount  of  coloring  principle  con- 
tained within   the  elementary   granules  of   the   cuticle,  and 
their  consequent  depth  of  hue.     In  the  negro,  the  granules 
are  more  or  less  black  ;  in  the  European  of  the  south,  they 
are  amber-colored  ;  and  in  the  inhabitants  of  the  north,  they 
are  pale  and  almost  colorless. 

646.  Color  of  the  skin  has  relation  to  energy  in  its  action  ; 
thus,  in  the  equatorial   region,  where  light  and   heat  are  most 
powerful,  the  skin  is  stimulated  by  these  agents   to  vigorous 
action,  and  color  is  very  deep  ;  while  in  the  temperate  regions, 
where  light  and  heat  are  not  so  intense,  the  lungs,  liver,  and 
kidneys  relieve  the  skin   of  part  of  its   duties.     The  colored 
layer  of  the   cuticle   has   been   called   the    re'te  mu-co'sum, 
(mucous  coat  of  the  skin,)  and  described  as  a  distinct  layer 
by  many  physiologists. 

Observation.  "  The  various  coloring  of  the  inner  layer  of 
the  cuticle  gives  to  some  animals  their  varied  hues  ;  the  ser- 
pent, the  frog,  the  lizard,  and  some  fishes  have  a  splendor  of 
hue  almost  equal  to  polished  metal.  The  gold-fish  and  the 
dolphin  owe  their  difference  of  color  and  the  brilliancy  of 
their  hues  to  the  color  of  this  layer  of  the  skin." 

647.  The  nerves  of  the  skin  are  the  organs  of  the  sense 
of  touch  and  feeling.     Through  them  we  receive  many  im- 
pressions that  enhance  our  pleasures,  as  the  grateful  sensa- 
tions imparted  by  the    cooling   breeze    in    a    warm  day.     In 


In  -what  season  of  the  year  is  the  coloring  matter  less  in  the  white  race  ? 
645.  To  what  is  the  color  of  the  skin  referable  ?  646.  Why  have  the  races 
of  the  torrid  zone  darker  complexions  than  those  of  the  temperate  or  frigid 
rones  ?  What  is  this  colored  layer  called  by  many  physiologists  ?  To 
\vhat  is  the  different  hues  in  animals  owing  ?  647.  Of  what  use  are  the 
nerves  of  the  skin  ? 


PHYSIOLOGY    OF    THE    SKIN. 


consequence   of  their    sensitiveness,  we  are 

tected,  by  being  admonished  of  the   proximity  of  destructive 

agents. 

Illustration.  A  man  who  had  been  afflicted  some  years 
with  a  severe  disease  of  a  portion  of  the  brain  and  spinal 
cord,  was  deprived  of  feeling  in  the  lower  extremities.  He 
was  directed  by  his  attending  physician  to  use  a  warm  foot- 
bath. Intending  to  follow  the  directions  given  him,  he 
immersed  his  feet  in  boiling  water,  which  he  supposed  of  a 
proper  temperature.  While  his  feet  were  immersed  in  the 
water,  he  experienced  no  sensation  of  an  unpleasant  nature. 
On  withdrawing  them,  he  was  astonished  to  find  the  cuticle 
separated  from  the  other  tissues,  by  the  effusion  of  serum, 
and  thus  producing  a  blister  over  the  whole  surface. 

648.  Portions  of  the  skin  would  suffer  every  day,  were  it 
not  for   the   sentinel-like    care    exercised  by  the   nerves,  by 
which  all  impressions  are  transmitted   to  the  brain.     As  the 
skin  is  continually  exposed   to    the    influence  of   destructive 
agents,  it  is  important  that  the  nerves,  provided   for  its  pro- 
tection, should  be  kept  in  a  healthy  state. 

649.  A  large  proportion  of  the  waste  of  the  body  passes 
through  the   outlets  of  the  skin  ;  some  portions   in  the  form 
of  oil,  others  in  the  form  of  water  and  carbonic  acid. 

650.  The  oil-glands  secrete  an  oil,  partly  free  and  diffused, 
and  partly  mixed   with  albumen.     When  the   cells  are  fully 
formed,    that  is,   fully    distended,  they    yield   their  contents, 
and  the  fluid  matter  they  contain  is  set  free,  and  passes  along 
the  tubes  to  the  surface  ;  this  fluid  matter  constitutes  the  oily 
element  of  the  economy  of  the  skin. 

651.  The  uses  of  the  unctuous  product  of  the  oil-glands 
are  twofold  :      1st.  The  protection  ;  2d.  The  removal  of  waste 

Give  the  illustration.  648.  "Why  is  it  necessary  that  the  cutaneous  nerves 
be  kept  in  a  healthy  state  ?  649.  Through  what  membrane  does  a  large 
proportion  of  the  waste  material  of  the  system  pass  ?  650.  What  is  the 
function  of  the  oil-glands?  651.  What  are  the  uses  of  the  oily  product 
of  these  glands  ? 


2<J8  ANATOMY,    PHYSIOLOGY,    AND    HYGIENK. 

mutter  from  the  system.  In  the  exercise  of  these  offices  the 
oily  substance  is  diffused  over  those  parts  of  the  skin  which 
are  naturally  exposed  to  vicissitudes  of  temperature  and 
moisture,  —  as  the  nose,  face,  and  head;  —  to  the  injurious 
attrition  of  contiguous  surfaces,  —  as  the  flexures  of  joints  :  — 
or  the  contact  of  acrid  fluids,  —  as  in  the  excoriations  to  which 
infants  are  liable. 

652.  The  oil   of  the  unctuous   substance   is  the   principal 
agent  in  effecting  these  purposes  :     1st.  It  prevents  the  evap- 
oration  or  congelation   of  the    water  of  the   cuticle,   which 
would  cause  it  to  become  parched  and  peel  off,  thus  leaving 
the  sensitive  skin  exposed.     2d.  It  affords  a  soft  medium  to 
the  contact  of  moving  substances.     3d.  It  repels  moisture  and 
fluids.     4th.  The  action  of  these  glands  removes  the  waste 
atoms  and  purifies  the  blood. 

653.  In  considering  the  purpose  of  the  oily  matter  of  the 
skin,  there  are  two  situations  in  which  it  deserves  especial 
remark.     1st.  Along  the  edges   of  the  eyelids,  where  it  is 
poured  out  in  considerable  quantity.     Here,  it  is  the  means 
of  confining  the  tears  and  moisture  of  the  eyes  within  the 
lids,  defending  the  skin  from  the  irritation  of  that  fluid,  and 
preventing  the  adhesion  of  the  lids,  which   is  liable  to  occur 
upon  slight  inflammation.     2d.  In  the  ears,  where  the  unctuous 
wax  not  only  preserves  the  membrane  of  the   drum  and  the 
passage  of  the  ear  moist,  but  also,  by  its  bitterness,  prevents 
the  intrusion  of  small  insects. 

654.  The  use  of  vhe  perspiratory  glands  is  to  separate  from 
the  blood  that  portion  of  the  waste  matter  which  is  carried 
off  through  the  skin  in   the   form    of  vapor.     Sa\ictorius,  a 
celebrated    medical    writer,  daily,  for  thirty  years,  weighed 

652.  What  prevents  the  evaporation  of  the  water  of  the  cuticle  ?  Give 
its  2d  use.  Its  3d.  Its  4th.  653.  What  is  said  in  reference  to  the  dis- 
tribution of  the  oily  matter  along  the  edges  of  the  eyelids  ?  In  the  ears  ? 
6o4.  Of  what  use  are  the  perspiratory  glands  ?  How  long  did  Sancton  us 
d;iilv  wfMtjh  his  food,  to  ascertain  the  amount  of  secretion  that  parsed 
tlii-iiii-ili  Hi*-  skin  : 


PHYSIOLOGY    OF    TII2    SKTN- 

himself,  his  food,  and  excretions.  He  estimated  that  jive  of 
every  eight  pounds  of  food  and  drink  passed  from  the  system 
through  the  many  outlets  upon  the  skin.  Many  place  the 
estimate  much  lower.  All  physiologists  agree  that  from 
twenty  to  forty  ounces  of  matter  pass  off  from  the  skin  of  an 
adult  every  twenty-four  hours. 

655.  The  average  amount  of  perspiration  is  about  thirty 
ounces ;  and  it  passes  off  in  such  minute  portions,  and  mixes 
so  rapidly  with  the  surrounding  air,  that  it  is  not  perceived. 
For  this  reason,  it  is  called  insensible  perspiration.     When 
this  excretion  is  increased,  it  forms  into  drops,  and  is  called 
sensible  perspiration.     The  following  experiments  prove  the 
existence  of  this  excretion  from  the  skin. 

Experiments.  1st.  Take  a  cold  bell-glass,  or  any  glass 
vessel  large  enough  to  admit  the  hand,  and  introduce  it  per- 
fectly dry ;  at  the  same  time  close  the  mouth  by  winding  a 
napkin  about  the  wrist ;  in  a  short  time,  the  insensible  per- 
spiration from  the  hand,  will  be  seen  deposited  on  the  inside 
of  the  glass.  At  first,  the  deposit  is  in  the  form  of  mist ;  but, 
if  the  experiment  be  continued  a  sufficient  time,  it  will  collect 
in  drops. 

2d.  Hold  the  apparently  dry  hand  near  a  looking-glass,  and 
the  invisible  vapor  will  soon  be  condensed,  and  cover  the  glass 
with  a  slight  dew. 

656.  It  is  important  that  this  excretion  be  maintained  with 
steadiness  and  regularity.     When  the  action  of  the  perspira- 
tory  glands    is   suppressed,  all    the   vessels  of  the   differen 
organs   will   suffer   materially,  and   become  diseased,  by  the 
redundant  waste  matter  that  should  be  carried  from  the  system. 
If  a   person   is   vigorous,  the   action   of  the    organs,  whose 


What  were  his  conclusions  ?  655.  What  is  the  average  amount  of  per 
spiration  every  twenty-four  hours  ?  What  is  insensible  perspiration  ? 
What  is  sensible  perspiration  ?  How  can  the  existence  of  the  excretion  of 
the  skin  be  shown  ?  Give  the  2d  experiment.  656.  Why  is  it  important 
that  these  excretions  be  maintained  regularly  ? 


:?no 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


functions  are  similar  to  those  of  the  skin,  as  channels  for 
the  exit  of  waste  matter,  will  be  increased,  and  thus  relieve 
the  diseased  state  of  the  hody.  But  the  over- taxing  of  these 
organs,  to  relieve  the  system,  often  produces  a  diseased  action 
in  themselves.. 

Fig.  117 


Fig.  117.  1,  1,  The  lines,  or  ridges  of  the  cuticle,  cut  perpendicularly.  2,  2,  2,  2,  2, 
_'))«  furrows,  or  wrinkles  of  the  same.  3,  The  cuticle.  4,  4,  4,  The  colored  layer  of  the 
cuticle.  5,  5,  The  cutis  vera.  6,  6,  6,  6,  6,  The  papillae.  7,  7,  Small  furrows  between 
the  papilla?.  8,  8,  8,  8,  The  deeper  furrows  between  each  couple  of  the  papilla;.  9,  9, 
v>!ls  filled  with  fat.  10,  10,  10,  The  adipose  layer,  with  numerous  fat  vesicles.  11, 
?.l,  11,  Cellular  fibres  of  the  adipose  tissue.  12,  Two  hairs.  13,  A  perspiratory  gland, 
with  its  spiral  duct.  14,  Another  perspiratory  gland,  with  a  duct  less  spiral.  15,  15, 
Oil-glands  with  ducts  opening  into  the  sheath  of  the  hair,  (12.) 


Note.  —  Let  the  pupil  review  the  anatomy  and  physiology  of  the  skip  'roro 
lg.  117  or  from  anatomical  outline  plate  No.  9. 


HYGIENE    OF    THE    SKIN.  301 


CHAPTER    XXXIII. 

HYGIENE    OF    THE    SKIN. 

657.  THE  sensibility  of  the  skin,  and  the  activity  of  the 
oil   and    perspiratory  glands,  are  modified  by  the  condition 
of  the  cuticle,  the  temperature  of  the   skin  and    body,  the 
purity  and  warmth  of  the  air,  and   the  character  of  the  light 
to  which  the  body  is  exposed.     Thus,  to  maintain  a  healthy 
action  of  every  part  of  this  membrane,  attention  should  be 
given  to  Clothing,  Bathing,  L  'ght,  and  Air. 

658.  CLOTHING,   in   itself,   does   not   bestow  heat,  but  is 
chiefly  useful  in  preventing  the  escape  of  heat  from  the  body, 
and  in  defending  it  from  the  temperature  of  the  atmosphere. 
In  selecting  and  applying  clothing  to  our  persons,  the  follow- 
ing suggestions  should  be  observed. 

659.  The  material  for  clothing  should  be  a  bad  conductor 
of  heat ;  that  is,  it  should  have  little  tendency  to  conduct  or 
remove  heat  from   the   body.     This  depends  mainly  on  the 
property  possessed  by  the  material  in  retaining  atmospheric 
air  in  its  meshes. 

660.  The    material  for  clothing    should   not  possess  the 
property  of  absorbing  and  retaining  moisture.     Dampness, 
or  moisture,  renders  apparel  a  good  conductor  of  heat;  beside, 
if  the  perspired  fluid,  and  the  saline  material  it  holds  in  solu- 
tion, are   readily  absorbed    by   the    clothing,  they  become 

657—716.  Give  the  hygiene  of  the  skin.  657.  What  influences  modify 
the  action  of  the  oil  and  perspiratory  glands  ?  To  what  must  atten- 
tion be  given  to  maintain  a  healthy  action  of  the  skin  ?  658.  What  is 
said  in  regard  to  the  clothing  ?  659.  Mention  a  property  that  the  material 
for  clothing  should  possess.  660.  What  property  in  the  selection  of  cloth 
ing  should  we  avoid  ?  Why  ? 

26 


302  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

sources  of  irritation  to  the  skin  with  which  the  apparel  comes 
in  contact. 

661.  Furs  contain  a  greater  amount  of  air  in  their  meshes, 
than  any  other  article,  and  they  absorb  no  moisture ;  conse- 
quently, as  an  article  of  dress,  they  are  best  adapted  to  those 
who  are  exposed  to  great  vicissitudes  of  heat  and  cold. 

662.  Woollen  cloth  retains  more  air  in   its  meshes  than 
any  other  article  except  furs  and  eider  down,  and  it  absorbs 
but  very  little  moisture.     These  properties,  together  with  its 
comparative  cheapness,  render  it  a  good  article  of  apparel  for 
all  classes  of  persons.     The  only  objection  to  its  general  use 
is,  the  disturbance  of  the   electricity  of  the   system,  and  the 
irritation  to  delicate  skins  from  the  roughness  of  its  fibres. 

Observation.  Flannels  are  not  only  beneficial,  during  the 
cold  season,  in  preventing  colds  and  rheumatism,  but  they  are 
of  great  utility  in  the  warm  season,  in  shielding  the  system 
from  the  chills  at  evening,  that  induce  disease  of  the  alimen- 
tary canal.  Their  general  use  among  children  and  delicate 
females,  would  be  a  preventive  of  the  "season  complaints" 
prevalent  in  the  months  of  August  and  September. 

663.  Cotton  contains  less  air  in  its  meshes  than  woollen, 
but  much  more  than  linen.     In  texture,  it  is  smoother  than 
wool,  and  less  liable  to  irritate  the  skin.     This  fabric  absorbs 
moisture  in  a  small  degree.     In  all  respects,  it  is  well  adapted 
for  garments  worn   next  the  skin.     When  woollen    flannels 
irritate  the  skin,  they  may  be  lined  with  cotton. 

664.  Silk  is  not  as  good  a  conductor  of  heat  as  cotton,  nor 
does  it  absorb  moisture  to  any  considerable  degree ;  its  texture 
is  smooth,  and  does  not  irritate  the  skin ;  consequently,  when 
the  garment  of  this  fabric  has  sufficient  body  or  thickness,  it 

661.  Give  the  properties  of  fur.  As  an  article  of  dress,  to  whom  are  they 
best  adapted  ?  662.  Give  the  properties  of  woollen  cloth.  Is  this  &  good 
article  for  clothing  ?  What  objection  ?  What  are  the  advantages  of 
wearing  flannels  ?  663.  What  are  the  qualities  of  cotton  as  an  article  of 
dross  r  664.  Of  silk  ? 


HYGIENE    OF    THE    SKIN.  303 

;s  a  good  article  for  clothing.  The  greatest  objection  to  its 
use  is  the  disturbance  of  the  electricity  of  the  system,  and 
its  )  »gh  price. 

665.  Linen  is  not  only  a    good   conductor   of  heat,  and 
consequently  a  poor  article  of  apparel,  but  it  likewise  absorbs 
the  fluids  carried  from  the  system  by  the  agency  of  the  oil 
and  perspiratory  glands.     When  garments  are  made  of  this 
material,  the  body  is  not  surrounded  by  a  layer  of  air,  but  by 
one  of  moisture.     This  still   further   increases  its    power  to 
conduct  heat  from  the  system,  rendering  it  a  very  objectiona- 
ble article  of  apparel,  even  in  warm  weather   and    in   hot 
climates,  where  the  dress  is  usually  thin. 

666.  Clothing   differs   in   its    power   of  radiating   heat. 
This  is  influenced  by  the  color  ;   those  articles   that  radiate 
heat  freely  also  absorb  it  readily.     A  black  surface  is  a  good 
radiator,  while  a  white  surface  is  not,  because  it  reflects  the 
calorific  rays.      It  is  obvious  that  those  colors  which  render 
the  transmission  of  external  heat  difficult,  must  impede  the 
transmission  of  caloric  from  the  body.     Thus  it  is  manifest, 
that  light-colored  apparel  is  best  adapted  for  every  season  and 
every  climate. 

Observation.  Coach-drivers  are  practically  aware,  that  in 
cold  weather,  light-colored  over-coats  are  warmest,  except 
when  they  are  exposed  to  the  direct  rays  of  the  sun,  or  when 
seated  before  a  warm  fire.  On  the  other  hand,  when  the 
temperature  is  elevated,  light-colored  apparel  is  coolest,  be- 
cause the  sun's  rays  are  then  reflected. 

667.  The  clothing  should  be  of  a  porous  character.     The 
skin  is  not  only  an  important  agent  in  separating  from  the 
blood  those  impurities  that  otherwise  would  oppress  the  system 
and  occasion  death,  but  it  exercises  great  influence  upon  the 
system,   by  receiving  oxygen  through  its  tissues,  and  giving 

G6o.  What  is  said  of  linen  as  an  article  of  apparel  ?  6G6.  Why  is  light- 
colored  apparel  best  adapted  for  every  season  ?  What  is  said  of  the  u(> 
parol  of  coach-drivors  ?  (507.  Why  should  wo  wear  porous  clothing  ? 


301  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

back  carbonic  acid  in  return.  Consequently,  the  apparel 
should  be  made  of  a  material  that  will  permit  free  trans- 
piration from  the  skin,  and  likewise  convey  the  excreted  fluids 
from  the  surface. 

6G8.  The  necessity  for  this  is  illustrated  in  wearing  India 
rubber  over-shoes.  If  they  are  worn  over  boots  ten  or  twelve 
hours,  not  only  the  hose,  but  the  boots  will  be  moist  from 
retained  perspiration,  and  the  residual  matter  left  in  contact 
with  the  skin  may  be  reconveyed  into  the  system  by  absorp  • 
tion,  causing  headache  and  other  diseases.  Cotton  and  wool- 
len fabrics  are  not  only  bad  conductors  of  heat,  but  are  also 
porous ;  for  these  reasons,  they  are  well  adapted  to  transmit 
the  excretions  of  the  skin. 

669.  The  clothing  should  be  not  only  porous,  but  jilted 
loosely.  The  garments  should  retain  a  layer  of  air  between 
them  and  the  body.  Every  one  is  practically  aware  that  a 
loose  dress  is  much  warmer  than  one  which  fits  closely  ;  that  a 
loose  glove  is  warmer  than  a  tight  one  ;  and  that  a  loose  boot 
or  shoe  affords  greater  warmth  than  one  of  smaller  dimen- 
sions. The  explanation  is  obvious ;  the  loose  dress  encloses 
a  thin  layer  of  air,  which  the  tight  dress  is  incapable  of 
doing ;  and  what  is  required,  is,  that  the  dress  should  be 
closed  at  the  upper  part,  to  prevent  the  dispersion  of  the 
warm  air,  by  the  ventilating  current  which  would  be  estab 
lished  from  below. 

Observation.  As  the  purpose  of  additional  garments  is  to 
maintain  a  series  of  strata  of  warm  air  within  our  plothing,  we 
should,  in  going  from  a  warm  room  into  the  cold  air,  put  on 
our  defensive  coverings  some  little  time  previous,  in  order 
that  the  layers  of  air  which  we  carry  with  us  may  be  suffi 
ciently  warmed  by  the  heat  of  the  room,  and  not  borrowed 
from  the  body  on  exposure  to  the  cold. 

668.  How  is  the  necessity  of  porous  clothing  illustrated?  669.  "Why 
should  we  wear  loose  garments  ?  What  is  the  use  of  additional  garments 
when  going  from  a  warm  to  a  cold  air  ?  When  should  they  be  put  on  ? 


HYGIENE    OF    THE    SKIN.  305 

670.  The  clothing  should  be  suited  to  the  temperature  of  the 
atmosphere  and  the  condition  of  the  individual.     The  invari- 
able rule  should  be,  to  wear  enough  to  maintain  an  equal  and 
healthy  action  of  the  skin.     Care  should  be  taken,  however, 
that  the  action  of  the  cutaneous  vessels  is  not  inordinately 
increased,  as  this  would  debilitate,  not  only  the  skin,  but  the 
internal  organs  of  the  system,  as  the  stomach  and  lungs. 

671.  No  rule  as  to  the  quantity  of  clothing  can  be  given, 
as  the  demand  will  vary  with  different  individuals.     The  fol- 
lowing are  among  the  most  prominent  causes  of  this  variation  : 
Those  persons  who  have  large,  active  brains,  full  chests,  well 
developed  lungs,  breathe  an  adequate  amount  of  pure  air,  and 
take  sufficient  food  to  supply  the  wants  of  the  system,  require 
less  clothing  than  those  of  an  opposite   character,  because 
more  heat  is  generated  in  the  system. 

672.  The  child  and  the  aged  person  require  more  clothing 
than  the  vigorous  adult.   "  Should  we  judge  from  observation, 
the  inference  would  be,  that  children  require  less  clothing 
than  adults.     This  is  an  error,  for  the  temperature  in  infancy 
is  not  only  lower  than  in  manhood,  but  the  power  of  creating 
heat  is  feebler.     The  same  remarks  are  applicable  to  those 
persons  who  have  outlived  the  energies  of  adult  life." 

Observation.  The  system  of  "  hardening  "  children,  by  an 
inadequate  supply  of  clothing,  and  keeping  them  uncomfort- 
ably cold  throughout  the  whole  day,  is  inhuman,  as  well  as 
unprofitable.  It  operates  upon  the  child  somewhat  like  the 
long-continued  chill  upon  a  certain  portion  of  the  farmer's 
herd,  that  are  kept  shivering  under  the  thatched  shed,  retard- 
ing the  growth  of  their  systems,  which  require  more  food  to 
satisfy  the  keen  cravings  of  hunger  than  when  they  are  com- 

670.  What  should  be  the  invariable  rule  in  reference  to  the  amount  o^ 
clothing  that  should  be  worn  ?  What  precaution  should  be  observed  ? 
671.  What  are  some  of  the  causes  of  the  variation  of  the  demand  for 
clothing  ?  672.  Why  do  the  child  and  aged  person  require  more  clothing 
than  the  vigorous  adult  ?  What  is  said  of  the  system  of  hardening 
children  ? 

$26  * 


306  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

fortably  sheltered.  To  make  the  boy  robust  and  active,  he 
must  have  nutritious  food  at  stated  hours,  and  free  exercise  in 
the  open  air,  and  his  system  must  be  guarded  from  chills  by  a 
due  amount  of  apparel. 

673.  More  clothing  is  needed  when  a  vital  organ  is  dis- 
eased.    It  may  be  observed  that  in  consumption,  dyspepsia, 
and  even  in  headache,  the  skin  is  pale  and  the  extremities 
cold,  because  less  heat  is  generated.     Thus  persons  affected 
with  these  complaints,  when  exposed  to  cold  air,  need  more 
clothing  than  those  individuals  whose  organs  are  not  diseased, 
and  the  functions  of  which  are  properly  performed. 

674.  More    clothing    is   required    in    the    evening,   than 
during  the  day.     In  the  evening  we  have  less  vital  energy, 
and  therefore  less  heat  is  generated  in  the  system,  than  in  the 
early  part  of  the   day ;  beside,  the  atmosphere  is  damp,  the 
skin  has  become  moist  from  free   perspiration,  and  heat,  in 
consequence,  is  rapidly  removed  from  the  system.     For  this 
reason,  when  returning  from  crowded  assemblies,  we  should 
be  provided  with  an  extra  garment. 

Observations.  1st.  If  there  is  a  chill  upon  the  system  after 
having  arrived  home,  warmth  should  be  restored  as  speedily 
as  possible.  This  can  be  done  by  friction  with  warm  flannels, 
and  by  using  the  warm  or  vapor  bath.  By  this  procedure, 
the  pernicious  effects  of  the  chill  will  be  prevented  before  any 
disease  is  fixed  upon  the  system.  Is  it  not  the  duty  of  the 
parent  and  the  guardian  to  learn  these  facts,  and  to  see  that 
they  are  not  only  learned,  but  reduced  to  practice  ? 

2d.  The  farmer  and  industrious  mechanic  would  be  freed 
from  many  a  rheumatic  pain,  if,  while  resting  from  their 
labors  at  evening,  or  taking  the  ordinary  meal  after  hard  toil,, 
they  would  put  on  an  extra  garment.  The  coat  might  not 

673.  Why  do  dyspeptic  and  consumptive  persons  require  more  clothing 
than  those  who  have  healthy  vital  organs  ?  674.  Why  do  we  need  more 
clothing  in  the  evening  than  during  the  day  ?  How  can  the  pernicious 
"fleets  of  a  chill  be  prevented  ?  Give  the  2d  observation. 


HYGIENE    OF    THE    SKIN.  307 

feel   so   agreeable  for    the  first  few   minutes,   b^t  it  would 
ultimately  conduce  to  health  and  longevity. 

675.  The  person  of  active  habits  requires  less  clothing  than 
one  of  sedentary  employments.     Exercise  increases  the  circu- 
lation of  the  blood,  which  is  always  attended  by  the  disen 
gagement  of  a  greater  quantity  of  heat ;  consequently,  an 
increase  of  warmth  is  felt  throughout  the  system.     We  like- 
wise need    more  clothing  while    riding,  than  when  we   are 
walking ;  because  the  exercise  of  the  former  is  less  than  that 
of  the  latter.     The  same  is  true  when  resting  in  the  field  or 
shop,  after  laborious  exercise. 

Observation.  We  need  a  greater  amount  of  clothing  while 
asleep,  than  during  'the  day ;  as  not  only  the  action  of  the 
body,  but  that  of  the  brain,  during  sleep,  is  suspended. 

676.  Less  clothing  is  required  when  the  cutaneous  surface 
is  clean.     A  film    of  impurities   obstructs    the    perspiratory 
ducts,  and    diminishes   the   action   of    their   glands ;   conse- 
quently, less  heat  is  generated.     For  this  reason,  the  hands 
or  feet  when  clean  are  less  liable  to  become  chilled  or  frozen. 

677.  The  sensitiveness  of  the  skin  to  the  influence  of  cold, 
is  much  modified  ly  habit.     A  person  who  has  been  habituated 
to  the  temperature  of  a  warm  room,  or  warm  climate,  suffers 
more  when  exposed  to  cold,  than  an  individual  who  has  been 
accustomed  to  colder   air.      Thus   a   person  who  labors  or 
studies   in  a  warm  room,  should  wear  more  clothing  when 
exposed  to  the  air,  while  walking  or  riding,  than  an  individual 
who  labors  in  a  cooler  atmosphere.     Not  only  is  the  sensi- 
bility of  the  skin  increased  by  a  warm  atmosphere,  but  the 
activity  of  the  digestive,  respiratory,  and  nervous  systems,  in 
generating  heat,  is  much  diminished.     This  is  an  additional 
reason  why  an  increased  amount  of  clothing  is  demanded 

675.  Why  does  the  person  of  active  habits  require  less  clothing  than  one 
of  sedentary  employments  ?  676.  Why  do  we  need  less  clothing  when 
tne  skin  is  clean  ?  677-  Show  the  effect  of  habit  on  the  sensitiveness  of 
the  ?kin. 


tf08  ANATOMY,    PHYSIOLOGY,    AND    HYOIENE. 

during  exposure  to  cold  air.  In  all  cases  where  practicable 
the  heat  of  the  system  should  be  maintained  by  exercise,  in 
preference  to  the  use  of  fur  or  flannel. 

678.  Those  parts  of  the  skin  usually  covered,  uniformly 
need    that    protection.      The    power   of   generating   heat    is 
diminished,  and  the  impressibility  to  cold  is  increased,  on  those 
portions  of  the  skin  usually  clothed.     If  a  person  wears  the 
dress  high  and  close  about  the  neck,  he  suffers  from  exposure 
to  a  cold  atmosphere  if  a  dress  is  worn  that  is  not  as  high  or 
more  open.     As  a  general  rule,  it   is   preferable  that  those 
parts  of  the  system,  as  the  larynx,  be  exposed  that  are  not 
uniformly  protected  by  clothing. 

679.  The  clothing  should  be  kept  clean.     No   article    of 
apparel  is  entirely  free  from  absorption  ;  even  wool  and  cotton 
possess  it  in  a  small  degree.     They  take  up  a  portion  of  the 
transpired  fluids  which  contain  saline  and  animal  matter,  and 
thus  the   fibres  of  the  garments  become   covered  with    the 
cutaneous  excretions.     We  are  practically  aware  of  the  reten- 
tion of  these  secretions  from  the  soiled  appearance  of  those 
garments  worn  next  the  skin,  which  are  so  covered  as  to  pre- 
clude the  particles  of  dust  from  lodging  upon  them. 

680.  The  porosity  of  the  clothing  is  lessened  when  soiled, 
and  its  power  of  conducting  heat  from  the  system  in  conse- 
quence, is  increased.     The  residual    matter  with  which  the 
clothing  is  coated  is  brought  in  contact  with  the  skin,  which 
causes  irritation,  and  not  unfrequently  re-absorption  of  the 
elements,  thrown  off  from  the  system   through  this  avenue. 
Hence    warmth,   cleanliness,    and    health    require    that    the 
clothing,   particularly  the    garments  worn  next  to  the  skin, 
should  be  frequently  and  thoroughly  washed.     This  should 
not  be  forgotten  in  regard  to  children,  for  their  blood  circu- 

678.  Why  do  those  parts  of  the  skin  usually  clothed  need  protection  ? 
679.  Why  should  the  apparel  be  kept  clean  ?  680.  What  effect  has  un- 
deanliness  upon  the  porosity  of  clothing  ?  What  is  said  in  reference  to 
the  clothing  of  children  t 


HYGIENE    OF    THE    SKIN.  309 

!at«;s  with  greater  rapidity  than  that  of  adults,  and  a  proper- 
tionably  greater  amount  of  waste  matter  is  thrown  off  from 
their  systems. 

681.  The  under -garments  worn  during  the  day  should  not 
be  worn  at  night,  or  the  reverse.     When  under-garments  arc 
vorn  several  successive  days  or  nights,  they  should  not  be  put 
n  drawers,  or  hung  up  in  a  close  closet,  as  soon  as  taken  from 

ihe  body,  but  should  be  exposed  to  a  current  of  air. 

682.  Occupied   beds   should  be   thoroughly   aired   in   the 
morning.     The  excretions  from  the  skin  are  most  abundant 
during  the  hours  of  sleep ;    and  if  the  sheets  and  blankets, 
together  with  the  bed,  are  not  aired  every  morning,  by  being 
so  arranged  that  both  surfaces  may  be  exposed  to  the  air,  the 
materials  eliminated   from   the  skin  will  be   retained  in  the 
meshes  of  the  bed-clothing,  and  may  be  conveyed  into  the 
system  of  the   next   occupant,  by   absorption.       Oftentimes 
diseases  of  a  disagreeable  nature  are  contracted  in  this  way. 
This  fact  should  be  instilled  into  every  mother's  and  daugh- 
ter's mind. 

Observation.  Bed -linen  should  not  be  put  on  a  bed  when 
it  is  not  sufficiently  dried,  or  contains  moisture  from  the  excre- 
tions of  the  skin,  nor  should  beds  or  bedding  be  slept  in,  that 
have  remained  in  a  damp  room  that  has  not  been  occupied  for 
many  weeks,  unless  the  dampness  is  removed  from  the  bed- 
linen  by  a  warming-pan,  or  in  some  other  way. 

683.  Changes  of  dress,  from  thick  to  thin,  should  always 
be  made  in  the  morning.     At  this  time  the  vital   powers  are 
usually  in  full  play.     Many  a  young  lady  has  laid  the  founda- 
tion of  a  fatal  disease,  by  disregarding  this  rule,  in  exchan- 
ging the   thick  dress,  with  woollen  stockings,  for  the   flimsy 
dress  and  hose  of  silk  or  cotton,  which  are  considered  suitable 

681.  Should  the  garments  worn  during  the  day  be  worn  at  night  ? 
682.  What  is  said  respecting  the  cleanliness  of  beds  and  bedding  ? 
Why  should  not  bed-linen  that  is  damp  be  slept  in  ?  683.  When  should 
change  of  dress  from  thick  to  thin  be  made  ?  Why  ? 


310  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

for  the  ball-room  or  party.  Sudden  changes  in  wearing- 
apparel,  as  well  as  in  food  and  general  habits,  are  attended 
with  hazard  ;  and  this  is  proportionate  to  the  weakness  or 
exhaustion  of  the  system  when  the  change  is  made. 

684.  Wfien  the  clothing  has  become  wet,  it  is  best  to  change 
it  immediately.  The  skin  should  then  be  rubbed  with  a  dry 
crash  towel,  until  reaction,  indicated  by  redness,  is  produced. 
If  the  garments  are  not  changed,  the  person  should  exercise 
moderately,  so  that  sufficient  heat  may  continue  to  be  gener- 
ated in  the  system  to  dry  the  clothing  and  skin  without  a  chill. 
Sitting  in  a  cool  shade,  or  current  of  air,  should,  by  all  means, 
be  avoided1;  as  colds  are  not  contracted  by  free  and  excessive 
exercise,  but  by  injudicious  management  after  such  exercise. 

Observation.  When  an  individual  has  been  thrown  into  a 
profuse  perspiration  by  violent  exercise,  though  the  skin  and 
clothing  may  become  wet,  he  feels  no  inconvenience  from  the 
dampness,  as  long  as  he  continues  that  amount  of  exercise 
for  the  reason  that  the  circulation  of  the  blood  being  increased 
heat  is  generated  in  sufficient  quantity  to  replace  the  amoun' 
abstracted  from  the  system  in  evaporating  the  free  perspira 
tion  ;  but  as  soon  as  the  exercise  is  discontinued,  the  increased 
circulation  subsides,  and  with  it  the  extra  amount  of  gener- 
ated heat.  This  accounts  for  the  chill  we  experience,  wher 
the  damp  clothing  is  permitted  to  dry  on  the  body,  after  tht* 
cessation  of  exercise. 

684.  "What  suggestion  when  the  clothing  has  become  wet  ?  What  should 
DO  done  if  the  garments  are  not  changed  ?  "What  causes  the  chill  that  i* 
experienced  when  damp  clothing  is  permitted  to  dry  on  the  body  ? 


HYGIENE    OF    THE    SKIN.  311 


CHAPTER     XXXIT. 

HYGIENE    OF    THE    SKIN,    CONTINUED. 

685.  BATHING,  its  necessity  and   expediency,   is    obvioua 
from  the  structure  and  the  functions  of  the  skin.     The  cuticle 
is  cast  off  in  minute,   powdery  scales,  many   of  which   are 
retained  upon  the  surface  by  the  pressure  of  clothing.     These 
mingle  with  the  oily  and  saline  products  of  the  skin,  and  form 
a  thin  crust.      This  crust,  on  account   of   its  adhesiveness, 
collects  particles  of  dust  and  soot  from  the  atmosphere,  and 
particles  of   foreign  matter  from  our  dress  ;  ^o   that  in  the 
course  of  the  day  the  whole  body  becomes  coated  with  im- 
purities.    If  this  coating  remains,  becomes  thick  and  estab- 
lished upon  the  skin,  it  will  produce  the  following  effects :  — 

686.  1st.    The  pores  will  be  obstructed,  consequently  trans- 
piration impeded,  and  the  influence  of  the  skin  as  an  excre- 
tory entirely  prevented.     When  the  pores  are  obstructed,  and 
transpiration  is  checked,  the  elements  of  the  transpired  fluids 
will  necessarily  be  retained   in  the  system  ;  and,  as  they  are 
injurious  and  poisonous  if  retained,  they  must  be  removed  by 
those  organs  whose  functions  in  the  animal  economy  are  sim- 
ilar, as  the  lungs,  kidneys,  liver,  intestines,  &c. 

687.  When  these  organs  are  called  upon  to  perform  their 
offices,  and  in  addition  that  of  another,  the  healthy  equilibrium 
is  destroyed,  and  the  oppressed  organ  will  suffer  from  exhaus- 
tion, and  become  the  prey  of  disease.    Thus,  obviously,  habits . 
of  uncleanliness  are  a  cause  of  consumption  and  other  seri- 

685.  Show  the  necessity  for  bathing.  686.  "What  effect  upon  the  body 
if  the  pores  of  the  skin  are  obstructed  ?  687.  "What  is  the  effect  when  an 
organ  not  only  performs  its  own  specific  function,  but  that  of  another  ? 


312  ANATOMY,    PHYSIOLOGY,  AND    HYGILNE. 

BUS  diseases  of  the  vital  organs.  Again,  obstruction  of  the 
pores  will  prevent  respiration  through  the  skin,  thus  depriving 
the  blood  of  one  source  of  its  oxygen,  and  one  outlet  of  its 
carbonic  acid,  which  will  diminish  the  temperature  of  the 
system,  and  the  same  results  follow  as  when  the  clothing  is 
inadequate. 

688.  2d.    The  retained  perspirable  matter  will  irritate  /At 
skin,  both  mechanically  and  chemically  ;  and  this  membrane 
will  be  kept  damp  and  cold,  from  attraction  and  detention  of 
moisture ;  and  foreign  material,  as  before  adverted  to,  once 
removed  from  the  system,  may  be  reconveyed  into  it  by  ab- 
sorption.    As  a  consequence,  cutaneous  eruptions  and  diseases 
will  be  produced,  and  the  re-absorption  of  matter  once  sepa- 
rated from  the  system,  will  be  the  exciting  cause   of  other 
injurious  disorders. 

689.  3d.  A  film   of  foreign   substance  on  the  skin  will 
inevitably   become  the    seat  of  detention    of   miasmata  and 
infectious  vapors.     These  will    remain    until    absorbed,  and 
engender  the  diseases  of  which  they  are   the  peculiar  cause. 
This  is  one    reason  why  filthy   persons   contract    infectious 
diseases  more  frequently  than  individuals  of   cleanly  habits. 

690.  Bathing   is  useful  to  promote  cleanliness.      In  this 
capacity,  it  enables  us  to  remove  the  coating  of   impurities 
from  the  exterior  of  our  persons.     It  effects  this  purpose   by 
dissolving  saline  matters,  and  holding  in  temporary  suspen- 
sion those  substances  which  are  insoluble. 

691.  The  cuticle  is  composed  of  a  substance  resembling 
the  dried  white  of  egg,  or,  in  a  word,  albumen.     This  is  solu- 
ble in  alkalies,  and  these  are  the  agents  which  are  commonly 
employed  for  purifying  the  skin.     Soap  is  a  compound  of  the 
alkali  soda  with  oil,  the  former  being  in  excess.     When  used 

688.  How  are  cutaneous  eruptions  frequently  produced  ?  689.  How 
are  infectious  vapors  transmitted  to  the  system  ?  690.  How  does  bath 
ing  promote  cleanliness  ?  691.  Why  is  it  necessary  to  use  soap  in 
bathing  ? 


HYGIENE    OF    THE    SKIN.  313 

for  washing,  the  excess  of  alkali  combining  with  the  oily  fluid, 
with  which  the  skin  is  naturally  bedewed,  removes  it,  in  the 
form  of  an  emulsion,  and  with  it  a  portion  of  any  adhering 
matter.  Another  portion  of  the  alkali  softens  and  dissolves 
the  superficial  layer  of  the  cuticle  ;  and  when  this  is  removed 
the  cuticle  is  free  from  impurities. 

692.  Every  washing  of  the  skin  with  soap  removes  the 
old   face  of  the  cuticle,  and  leaves  a  new  one ;    and  were 
the  process  repeated  to  excess,  the  latter  would   become  sc 
thin  as  to  render  the  body  sensible  to  impressions  too  slight 
to  be  Felt  through  its  ordinary  thickness.     On  the  other  hand, 
when  the  cuticle  and  its  accumulated  impurities  are  rarely 
disturbed,  the  sensitiveness    of  the    skin  is    impaired.     The 
proper  inference  to  be  drawn  from  the  preceding  remarks,  is 
in  favor  of  the  moderate  use  of  soap  to  cleanse  the  skin. 

Observation.  If  any  unpleasant  sensations  are  felt  after  the 
use  of  soap,  they  may  be  immediately  removed  by  washing  the 
•surface  with  water  slightly  acidulated  with  lemon-juice  or 
vinegar,  which  neutralizes  the  alkali  that  may  remain  on 
the  skin.  This  is  effective  treatment  for  "  chapped  hands." 

693.  Bathing  may  be  partial  or  general,  and  the  water 
used  may  be  cold,  temperate,  tepid,  ivarm,  or  hot.     A  person 
may  apply  it  to  his  system  with  a  sponge,  it  may  be  poured 
upon  him,  or  he  may  immerse  himself  in  it.     The  simplest 
mode  of  bathing  is  to  apply  water  to  a  small  extent  of  sur- 
face, by  means  of  a  wet  sponge,  and  after  being  wiped  dry, 
again  cover  with  the  dress.     In  this  way  the  whole  body  may 
be  speedily  subjected  to  the  influence  of  water,  and  to  no  less 
useful  friction.     The  water  used  may  be  warm  or  cold.     This 
species  of   bathing    may  be    practised  by  any  invalid,  ana 


692.  Why  should  only  a  moderate  amount  of  soap  be  used  in  bathing  ? 
If  unpleasant  sensations  are  felt  from  too  free  use  of  soap,  how  can  they 
be  counteracted  ?  693.  Give  the  different  forms  of  bathing.  What  is  the 
simplest  mode  of  bathing  ?  Can  this  mode  be  adopted  by  invalids  with 
safety  ? 

27 


314  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

always  with  benefit,  if  the  bathing  is  succeeded  by  a  glow  of 
warmth  over  the  surface  ;  and  this  is  the  test  by  wnich  the 
benefit  of  all  forms  of  bathing  is  to  be  estimated 

694.  When  the  heat  of  the  system  is  adequate,  the  bather 
may  stand  or  sit  in  a  shallow  tub,  while  he  receives  the  water 
from   a  sponge  squeezed  over  the  shoulders  or  against   the 
body.     In  this  form  of  bathing,  the  person  is  more  exposed  to 
the  cold  air,  and  on  this  account  it  is  less  suitable  for  very 
fneble   individuals   than  the  first-mentioned  method.     In  the 
early  use  of  this  form  of  the  sponge-bath,  the  bather  should 
content  himself  with  a  single  affusion  from  the  sponge  ;  the 
body  should   be  quickly  wiped  with  a  soft  towel,  and  friction 
applied  with  a  crash  towel  or  a  brush. 

695.  The  third  kind  of  bathing  is  that  of  the  shower-bath, 
which  provides  a  greater  amount  of  affusion  than  the  former, 
combined  with  a  greater  shock  to  the  nervous  system.     The 
concussion  of  the  skin  by  the  fall  of  water,  particularly  dis- 
tinguishes this  from  the    previous   modes  of    bathing.     The 
degree  of  concussion  is  modified  by  the  size  of  the  openings 
through  which  the  water  issues,  and  the  height  of  the  reser- 
voir.    The  shower-bath  admits  of  modification,  adapting  it  to 
the  most  delicate  as  well  as  the  robust.     The  extent  of  fall, 
the  size  of  the  apertures,  the  quantity  and  temperature  of  the 
water,  may  be  regulated  at  pleasure. 

Observation.  In  using  the  shower-bath,  it  would  be  judi- 
cious to  commence  with  warm  or  tepid  water,  for  which,  by  a 
gradual  process,  cold  water  may  be  substituted.  In  this  way 
the  system  may  be  inured  to  cold  water.  After  bathing,  the 
skin  should  be  wiped  dry  and  rubbed  briskly. 

696.  The  fourth  form  of  bathing  is  that  in  which  the  body, 
or  a  portion  of  it,  is  immersed   in  water.     The  temperature 

What  is  the  test  by  which  to  estimate  the  benefit  of  all  modes  of  bath- 
ing ?  694.  Give  another  method  of  sponge-bathing.  695.  What  is  said 
of  the  shower-bath  ?  What  caution  is  given  ?  696.  Give  the  fourth  fon& 
of  bathiiig. 


HYGIEJNE    OF    THE    SKIN.  315 

of  the  water  in  this  form  of  bathing  may  be  modified  accord- 
ing to  the  sensations  and  purposes  of  the  bather.  This  form 
of  bathing  is  designated  according  to  the  heat  of  the  water. 
When  the  temperature  is  below  75°,  it  is  termed  a  cold  bath; 
when  from  75°  to  85°,  a  temperate  bath  ;  from  85°  to  95°,  a 
tepid  bath;  from  95°  to  98°,  a  warm  bath;  from  98°  to  105°, 
a  hot  bath.  In  using  this  form  of  bathing,  the  skin  should 
be  wiped  perfectly  dry,  and  briskly  rubbed. 

Observation.  The  length  of  time  a  person  may  remain  in 
a  cold  bath  with  benefit  varies  from  two  to  ten  minutes ; 
while  a  person  may  remain  in  a  temperate,  tepid,  or  warm 
bath,  from  ten  to  thirty  minutes,  or  until  special  indications 
are  exhibited. 

697.  In  the  vapor-bath,  the  vapor  is  not  only  applied  to  the 
exterior  of  the  system,  but  it  is  inhaled  and  brought  in  con- 
tact with  every  part  of  the  interior  of  the  lungs.     The  bather 
is  seated  upon  a  chair,  and  the  vapor  gradually  turned  on 
around   him,  until  the  proper  temperature    (90°  to  110°)   is 
attained.     The   bath  may   be   continued    from   ten  to  thirty 
minutes.     After  leaving  the  bath,  attention  should  be  given  to 
the  skin,  as  in  other  forms  of  bathing. 

698.  In  order  to  increase  and  promote  reaction  of  the  skin, 
various    measures  arid    processes  are  used,  some  of  which 
are  practised  in,  and  others  after,  quitting  the  bath.     Of  the 
former,  the  rubbing  and  brushing  the  skin  are  the  most  com- 
mon and   important.     The  brisk  and  efficient  friction  of  the 
skin  with  a  coarse  towel  and   flesh-brush,  after  quitting  the 
hath,  should  never  be  omitted.    This  short  catalogue  embraces 
al!  the  appliances  requisite  for  the  purpose. 

699.  Bathing  promotes  health  by  its  immediate  and  remote 

What  degree  of  temperature  of  water  is  termed  a  cold  bath  ?  A  tera 
perate  ?  A  tepid  ?  A  warm  ?  A  hot  bath  ?  State  the  length  of  time 
that  a  person  should  remain  in  the  different  baths.  697-  "What  is  said  of 
the  vapor  bath?  698.  Mention  the  different  methods  for  promoting  reac- 
tion of  the  skin. 


316  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

physiological  effects  on  the  system.  When  the  body  is  moist- 
ened with  a  sponge  wet  with  cold  water,  or  when  an  affusion 
by  the  sponge  or  shower-bath  is  used,  the  skin  instantly 
shrinks,  and  the  whole  of  its  tissue  contracts.  This  con- 
traction diminishes  the  capacity  of  the  cutaneous  system  of 
blood-vessels,  and  a  portion  of  the  blood  circulating  through 
them  is  suddenly  thrown  upon  the  more  internal  parts  of  the 
body.  The  nervous  system,  among  others,  participates  in  it, 
and  ij  stimulated  by  the  afflux,  and  communicates  its  stimulus 
to  the  whole  system.  This  causes  a  more  energetic  action  of 
the  neart  and  blood-vessels,  and  a  consequent  rush  of  blood 
back  to  the  skin.  This  is  the  state  termed  reaction,  the  first 
object  and  purpose  of  every  form  of  bathing. 

700.  This  condition  of  the  skin  is  known  by  the  redness 
of  the  surface,  the  glow,  comfort,  and  warmth  which  follow 
the    bath.     The  bather  should  direct  all  his  care  to  insure 
this  effect.     By  it  the  internal  organs  are  relieved,  respiration 
is  lightened,  the  heart  is  made  to  beat  calm  and  free,  the  mind 
is  clear  and  strong,  the  tone  of  the  muscular  system  is  in- 
creased, the  appetite  is  sharpened,  and  the  whole  system  feels 
invigorated.     This  is  the  end  and  aim  of  the  bather,  and  to 
this  all  his  training  tends.     The  error  is,  to  expect  the  result 
without  the  preparation. 

701.  In  order  to  promote  reaction,  and  to  be  efficient  in 
preserving  health,  bathing  should  be  regular,  should  be  com- 
menced by  degrees,  and  increased  by  a  process  of  training, 
and  should  not  be  permitted  to  intrude  upon  hours  devoted  to 
some  important  function,  as  digestion.     It  must  not  precede 
or  follow  too  closely  a  meal,  or  severe   mental  or  muscular 
exercise,  as  reaction  is  less  certain  and  vigorous  when  im- 


699.  What  is  the  effect  upon  the  skin  when  cold  water  is  applied? 
What  is  the  first  object  and  purpose  of  every  form  of  bathing  ?  700.  How 
is  this  condition  of  the  skin  known  ?  Mention  the  salutary  effects  that  this 
condition  has  on  the  body.  701.  How  should  bathing  be  performed,  in 
order  to  be  efficient  in  preserving  health  ? 


HYGIENE    OF    THE    SKIN.  317 

portant  internal  organs  are  employed,  than  when  they  are  at 
rest.  When  the  vital  powers  are  greatest,  and  the  system 
most  free  fiom  exhaustion,  bathing  is  most  beneficial  ;  hence 
the  morning  is  preferable  to  the  evening,  and  the  middle  of 
the  forenoon  to  the  middle  of  the  afternoon,  for  this  healthful 
and  agreeable  duty ;  as  the  vital  action  of  the  system  is  most 
energetic  in  the  early  part  of  the  day. 

702.  In  regard  to  the  frequency  of  bathing,  the   face  and 
neck,  from  their  necessary  exposure  to  the  atmosphere,  and 
the    impurities  which  the  latter    contains,  should  receive  at 
least  two  washings  in  twenty-four  hours,  one  of  which  should 
be  with  soap  ;  the  feet,  from  the  confined  nature  of  the  cover- 
ings which  are  worn  over  them,  require  at   least  one ;  the 
armpits,  from  the  detention,  as   well   as   from   the    peculiar 
properties  of  the  secretions,  at  least  one ;  and  the  hands  and 
arms,  as  many  as  seem  proper.     The  whole  person  should  be 
bathed  at  least  every  second  day,  but  the  most  perfect  health 
of  every  part  of  the  body  would  be  maintained,  if  the  excre- 
tions from  the  skin  were  removed  daily. 

703.  In  diseases  of  the  skin  and  internal  organs,  bathing 
is  a  remedial  measure  of  great  power.     It  should  never  be 
neglected  or  omitted.     It  is  not  only  pleasant  and  safe,  but  is 
really  more  effective  than  any  medicine  administered  inter- 
nally.    This,  like  other  curative  means,  should  be  applied  by 
the  direction  and  under  the  eye  of  the  medical  adviser,  that 
it  may  be  adapted  to  the  condition  of  the  patient. 

704.  "  From  the  first  hour  of  man's  existence  to  his  lates* 
breath,  in  health  and  in  sickness,  rich  or  poor,  water  is  always 
requisite.     Baths  were  dedicated  by  the  ancients  to  the  divini- 
ties of  medicine,  strength,  and  wisdom,  namely,  ^Esculapius, 
Hercules,  and  Minerva,  to  whom  might  properly  be  added  the 
goddess  of  health,  Hygeia.     The    use    of   water   has   been 

When  should  bathing  be  performed  ?  702.  How  often  should  we  bathe  ? 
70;;.  What  is  said  of  bathing  in  disease  ?  Who  should  direct  the  kind  of 
b;iih  proper  in  different  diseases  ?  704.  Were  baths  dedicated  by  th« 
ancients  ?  # 


318  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

enforced  as  a  religious  observance,  and  water  has  been  adopted 
as  one  of  the  symbols  of  Christianity." 

705.  The  AIR  is  an  agent  of  importance  in  the  functions  of 
the  skin.     It  imparts  to  this  membrane  oxygen,  and  receives 
from  it  carbonic  acid.     It  likewise   removes   from   it  a  large 
portion  of  the  perspiration  and  the  more  fluid  portions  of  the 
oily  secretion.     In  order  that  the  air  may  accomplish  these 
er  ds,  it  is  necessary  that  it  come  in  contact  with  the  body. 
This  is  one  of  the  many  reasons  why  we  should  wear  loose 
and  porous  clothing. 

706.  Again,  the  air  should  be  pure,  and  free  from  redun- 
dant moisture.     In   the  warm  mornings  of  July  and  August, 
the  air  is  loaded  with  moisture  and  impurities,  and  the  perspi- 
rable matter  is  not  removed  from  the  system  as  it  is  when  the 
air  is  pure  and  dry.     This  is  the  cause  of  the  general  lassitude 
that  is  experienced  during  such  mornings.     As  soon  as  the 
fog  is  dispelled,  these  unpleasant  sensations  are  removed.    To 
sustain  the  functions  of  the  skin  in  a  healthy  state,  the  parlor, 
kitchen,  sleeping-room,  school-house,  and  work-shop,  should 
be  well  ventilated.     The  blood  of  the  system  will  be  purer, 
and  its  color  of  a  brighter  scarlet,  if  the  skin  is  surrounded 
oy  fresh  and  pure  air,  than  when  it  is  foul  or  moist. 

707.  The  LIGHT  permeating  the  skin,  not  only  exercises  a 
salutary  influence  upon  this  membrane,  but  upon  the  blood, 
and,  through  this  fluid,  upon   the  whole    system.     For  this 
reason,  the  kitchen  and  the  sitting-room,  which  are  the  apart- 
ments most  used  by  ladies,  should  be  selected  from  the  most 
pleasant  and  well-lighted  rooms  in  the  house.     On  the  other 
hand,  dark  rooms  and  damp  cellar-kitchens  should  be  avoided, 
as  exercising  an  injurious  influence  upon  both  body  and  mind. 

708.  The  dark,  damp  rooms,  so  much  used  in  cities  and 

7)5.  Give  the  reasons  why  pure  air  should  be  supplied  to  the  skin 
706.  What  is  the  cause  of  the  general  lassitude  in  a  damp,  warm  morn- 
ing ?  707.  Show  the  salutary  effects  of  light  on  the  skin.  708.  What  is 
one  cause  of  disease  and  suffering  in  large  villages  ? 


HYGIENE    OF    THE    SKIN.  319 

large  villages,  by  indigent  families  and  domestics,  are  fruitful 
causes  of  disease,  as  well  as  of  vice,  poverty,  and  suffering. 
Common  observation  shows  that  solar  light  also  exercises  much 
influence  upon  the  vigor  and  color  of  vegetables.  Plants 
that  are  kept  in  well-lighted  rooms,  have  darker  and  more 
brilliant  colors  than  those  that  grow  in  darkened  apartments. 

709.  BURNS  and  SCALDS  are  terms  applied  to  those  condi- 
tions of  the  skin  which  are  produced  by  the   application  of 
an  undue  amount  of  heat,  which  changes  the  action  of  its 
vessels. 

710.  A  small  degree   of  heat  will  irritate  the  nerves,  and 
cause   an    increased    action   of   the    blood-vessels.     This    is 
attended   with  severe  smarting  pain,  and  will  be  followed  by 
the  deposition  of  serum  under  the  cuticle,  unless  applications 
are   made    immediately,  to  prevent  vesication,  or  blistering. 
To  prevent  or  suppress  this  state  of  arterial  action,  wet  some 
folds  of  cotton  or  woollen  cloth  with  cold   water,  and  apply 
them  to  the  parts  scalded  ;  continue  to  apply  cold  water,  so  as 
to  steadily  maintain   the  low  temperature  of  the  applications, 
as  long  as  the  smarting  pain  is  experienced.     The  steady 
application  of  cold  dressing  also  tends  to  prevent  an  increased 
action  of  the  blood-vessels,  and  will  suppress  it,  if  it  already 
exist. 

711.  When  blisters  are  formed,  the  cuticle   is  separated 
from  the  other  tissues  of  the  skin  by  the  effusion  of  serum. 
In  all  cases,  if  this  layer  of  the  skin  is  not  removed,  a  small 
opening    should   be  made    in  the  raised    cuticle,   by  which 
the  serum  deposited  may  be  removed.     Under  such  circum- 
stances, never  remove  the  cuticle,  as  it  makes  the  best  possi- 
ble covering  for  the  blood-vessels  and  nerves  of  the  true  skin. 
The    cold   water   dressing,  recommended    in   the    preceding 

709.  To  what  condition  of  the  skin  are  the  terms  burns  and  scalds  applied  ? 
710.  What  is  the  effect  when  only  a  small  degree  of  heat  is  applied  to  thf 
skin  ?  How  can  vesication  be  prevented  ?  711-  What  should  be  the  treat 
tuent  when  blisters  are  formed  ? 


,]X.'0  A.NATG.MV,    PJH  VSI OLOGY,    AAr  D    HV'HKNE. 

paragraph,  may  then  be  applied  as  long  as  the  smarting  sensa 
tion  continues.     After  the  pain  has  subsided,  the  blistered  par' 
may  be  covered  by  a  patch  of  cotton  or  linen  cloth,  upon 
which   an  ointment,  made    of  lard   and  bees-wax,  has   been 
spread. 

712.  If  the  cuticle  has  been  removed,  there  will  be  much 
suffering,  because  the  nerves  are  unduly  stimulated   by  the 
air.     The  cuticle  is  the  sheath  or  covering  of   the  vessels 
and  nerves  of  the  skin,  and  when  it  is  removed,  a  substitute 
should  be  applied.     This  substitute  should  be  soothing,  and 
cover  the  denuded  surface.     Linseed-meal  or  ground  slippery- 
elm  bark  poultice,  fresh  cream,  or  lard  and  bees-wax,  spread 
upon  linen  or   cotton   cloth,  would  make  a    good    dressing. 
When  dressings  are  applied,  they  should  not  be  removed  until 
they  become  dry  and  irritating. 

713.  If  there  is  much  suffering,  administer  to  an  adult  from 
twenty-five   to   sixty   drops  of  laudanum,  according   to   the 
severity  of  the   pain.     If  the  patient  is  a  child,  from  fifteen 
drops  to  a  tea-spoonful  of  paregoric  may  be   administered. 
When  there  is  much  prostration,  some  hot  peppermint  tea  or 
other  stimulant  may  be  found  necessary  to  bring  on  reaction. 

714.  The  hands,  feet,  ears,  &c.,  are  subject,  in  cold  lati- 
tudes, to  be  frozen,  or  frost-bitten.     This  may  occur  when  the 
patient,  at  the  moment,  is  not  aware  of  it.     The  part  affected 
at  first  assumes  a  dull  red  color,  which  gradually  gives  place 
to  a  pale,  waxy   appearance,  and  becomes  quite  insensible. 
The  first  thing  to  be  done  in  such  cases,  is  to  reestablish  cir- 
culation.    This  should  be  effected  very  gradually.     If  a  large 
quantity   of  blood  is  thrown  suddenly  into  the    chilled   anil 
debilitated  vessels  of  the  frozen   part,  inflammation  may  be 
produced  that  will  destroy  the  vitality  of  the  limb. 

712.  "What  should  be  the  treatment  if  the  cuticle  has  been  removed  ? 
How  often  should  the  dressing  of  burns  be  removed  ?  713.  "What  may  be 
necessary  when  there  is  much  suffering?  714.  What  is  the  appearance  of 
limbs  while  freezing  ?  How  should  the  circulation  be  at  first  reestablished  r 
What  should  be  avoided  ? 


HYGIENE    OF    THE    SKIN.  32 1 

715.  The  circulation  and  sensibility  may  be  restored   by 
rubbing  the  frozen  limb,  with  snow,  or,  when  this  is  not  to  be 
obtained,  cold  water  ;    but  snow  is   always  to  be  preferred. 
The  fire  should  be  avoided ;  and  it  would   be  better  for  the 
patient  to  be  kept  in  a  cold  room,  for  a  time,  where  there  is 
no  fire,  or  where  the  temperature  is  moderate. 

716.  When  a  person   is  found  benumbed  with  cold,  and 
almost  or  quite  insensible,  he  should  be  taken  into  a  cold  room, 
the  clothing  removed,  and  friction  commenced  and  continued 
for   some   time,  with   snow.      When   warmth   begins    to   be 
restored,  the  individual  should  be  rubbed  with  dry  flannel,  and 
the  friction  continued  until  reaction  takes  place. 

Observation.  When  the  toes  and  heels  have  been  repeat- 
edly chilled,  there  may  be  produced  a  disease  called  chil- 
blains. This  affection  is  attended  with  tenderness  of  the  parts, 
accompanied  with  a  peculiar  and  troublesome  itching.  The 
prevention  of  this  disease  is  in  wearing  warm  hose  and  thick 
shoes  of  ample  size.  Bathing  the  feet  morning  and  evening 
is  also  a  prevention  of  this  disagreeable  affection.  When 
chilblains  exist,  apply  cold  water,  warm  camphorated  spirits, 
or  turpentine  linament. 

715.  How  may  the  circulation  and  sensibility  be  restored  ?  716.  "What 
treatment  should  be  adopted  when  a  person  is  benumbed  with  cold  ?  What 
treatment  should  be  adopted  when  warmth  begins  to  be  restored  ?  What 
is  said  of  chilblains  ? 


322  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

CHAPTER    XXXV. 

APPENDAGES    OF    THE    SKIN. 

717.  THE  HAIRS  are  appendages  of  the  skin,  and,  like 
the  cuticle,  they  are  a  product  of  secretion.  They  have  no 
blood-vessels  or  nerves,  and,  consequently,  no  vitality.  The 
hairs  take  their  origin  from  the  cellular  membrane,  in  the 
form  of  bulbs.  Each  hair  is  enclosed  beneath  the  surface 
by  a  vascular  secretory  follicle,  which  regulates  its  form  dur- 
ing growth.  In  texture,  it  is  dense,  and  homogeneous  toward 
the  circumference,  and  porous  and  cellular  in  the  centre,  like 
the  pith  of  a  plant.  Every  hair  has  on  its  surface  pointed 
barbs,  arranged  in  a  spiral  manner,  and  directed  toward  the 
root  of  the  hair ;  so  that,  if  a  hair  be  rolled  between  the  fin- 
gers, it  moves  only  in  one  direction. 


Pig.  118.  The  hair  follicle  (1)  is  represented  as  imbedded  in  the  cellular  membrane, 
(2,)  which  is  situated  beneath  the  skin.  3,  3,  The  membranous  sac,  which  has  a 
narmw  neck,  opening  externally  by  a  contracted  orifice,  through  which  the  hair  (4J 
passes.  Its  internal  surface  is  smooth,  and  not  adherent  to  the  hair,  but  separated  from 
it  by  a  reddish  fluid.  From  the  bottom  of  the  sac  (5)  the  pulp  of  the  hair  arises,  and 
passes  through  the  skin  at  6. 

717 — 723.  Describe  the  appendages  of  the  skin.  717.  Why  have  not  hairs 
vitality?  Where  do  they  take  their  origin?  Give  their  structure.  What 
is  represented  «>y  fig.  118? 


APPENDAGES    OF    THE    SKIN.  323 

718.  The   color  of  ihe  hair  varies  in  different  individuals, 
and  is  generally  supposed  to  depend  on  the  fluids  contained 
in  the  pith.     There  are  two  causes  which  act  in  changing 
the  hair  gray.     The  first  is,  defective  secretion  of  the  color- 
ing fluid.     The  second  is,  the  canals,  which  Convey  the  fluid 
into  the  hair,  become  obliterated.     In  the  first  instance,  the 
hair  will  remain  ;  in  the  second,  it  dice,  and  drops  out ;  the 
cuticle  of  the  scalp  grows  over  the  canal,  which  is  soon  oblit- 
erated, and  the  head  becomes  bald. 

Observation.  It  is  related  that  the  hair  of  Marie,  Antoinette, 
Queen  of  France,  and  others,  from  excessive  mental  agita- 
tion, changed  from  black  to  gray  in  a  single  night.  This  is 
not  strictly  true ;  the  secretion  may  be  arrested,  but  that 
already  deposited  in  the  pith  will  require  days  or  weeks  to  be 
removed. 

719.  Upon  the  upper  part  of  the  head,  the  oil-tubes  open 
into   the   hair-sacs ;  consequently,   the   secretion   of  the  oil- 
glands  is  spread  over  the  surface  of  the  hair,  and  not  upon 
the  cuticle.     This    is  the  cause    of  the    dry,  white,  branny 
scales,  called  "  scurf,"  or  "  dandruff,"  upon  the  head.    This 
is  natural,  and  cannot  be  prevented.     When  scurf  exists,  the 
only  necessary  application  to  remove  it,  is  the  frequent  use 
of  the  hair-brush,  and  washing  with  pure  water. 

Observation.  The  secretion  of  the  oil-glands  may  become 
impacted  around  the  hairs  as  they  issue  from  the  skin,  and 
thus  prevent  their  outward  movement  in  growing.  The 
pressure  of  the  matter  deposited  at  their  bulbs  will  then  cause 
itching.  The  comb  and  the  brush  may  be  used  to  remove  the 
impacted  matter,  and  relieve  the  disagreeable  sensation. 

720.  The  oil  is  most  abundant  near  the  roots  of  the  hah 


718.  Upon  what  does  the  color  of  the  hair  depend  ?  What  are  the  cause* 
of  the  hair  becoming  gray  ?  What  is  the  cause  of  the  hair  dropping  out  ? 
What  is  related  of  Marie  Antoinette?  719.  How  is  "dandruff"  on  tne 
scalp  produced?  What  is  the  only  necessary  application  to  remove  it  t 
Give  observation.  720.  Where  is  the  oil  of  the  hair  most  abundant  ? 


ANATOMY      PHYSIOLOGY,    AND    HYGIENE. 

A.  free  use  of  the  brush  spreads  it  along  the  hairs,  and  gives 
them  a  smooth,  glossy  appearance.  Soap  should  rarely .  be 
used  in  washing  the  head,  as  it  will  remove  the  oil  which  is 
essential  to  the  health  and  appearance  of  the  hair. 

721.  The  uses  of  the  hair  vary  in  different  regions  of  the 
body.  Upon  the  herd,  it  aids  in  shielding  the  brain  from 
injury  by  blows,  and  it  likewise  serves  to  protect  this  part 
of  the  system  from  heat  and  cold,  thus  maintaining  equal 
temperature  of  the  cerebral  organ.  About  the  flections  of  the 
joints,  as  in  the  axilla,  (armpit,)  they  prevent  irritation  of  the 
skin  from  friction  ;  in  the  passages  to  the  ears  and  nostrils,  they 
present  an  obstacle  to  the  ingress  of  insects  and  foreign  bodies ; 
while  in  the  eyebrows  and  eyelids,  they  serve  to  protect  the 
organ  of  vision. 

Fig.  119. 


Fig.  119.  A  section  of  the  end  of  the  finger  and  nail.  4,  Section  of  the  last  bona 
of  the  finger.  5,  Fat,  forming  the  cushion  at  the  end  of  the  finger.  2,  The  nail. 
1,  1,  The  cuticle  continued  under  and  around  the  root  of  the  nail,  at  3,  3,  3. 

722.  The  NAILS  are  hard,  elastic,  flexible,  semi-transparent 
scales,  and  present  the  appearance  of  a  layer  of  horn.     The 
nail  is  divided  into  the  root,  the  body,  and   the  free  portion. 
The  root  is  that  part  which  is  covered  on  both  surfaces  ;  the 
body  is  that  portion  which  has  one  surface  free ;  the  free  por- 
tion projects  beyond  the  end  of  the  finger. 

723.  The  nail  is  formed  of  several  laminse,  or  plates,  that 
are  fitted  the  one  to  the  other ;  the   deepest  is  that  which  is 
last  formed.     The  nails,  as  well  as  the  hoofs  of  animals  and 

How  can  it  be  spread  along  the  hairs  ?  Why  should  soap  not  be  used 
in  washing  the  hair  ?  721.  Of  what  use  is  the  hair  upon  the  head  ?  About 
the  flexions  of  the  joints  ?  In  the  nasal  and  ear  passages  ?  Upon  the  eye- 
brows and  eyelids  ?  722.  Describe  the  nails.  723.  How  are  they  forrred  "» 


APPENDAGES    OF    THE    SKIN.  325 

the  cuticle,  are  products  of  secretion.  They  receive  no  blood- 
vessels  or  nerves.  If  the  cuticle  be  removed  in  severe  scalds 
they  will  separate  with  it,  as  the  hoofs  of  animals  are  removed 
by  the  agency  of  hot  water.  The  nails  increase  in  length 
and  thickness,  by  the  deposition  of  albumen  upon  their  under 
surface,  and  at  their  roots,  in  a  manner  similar  to  the  growth 
of  the  cuticle,  of  which  they  constitute  a  part. 

Observations.  1st.  The  nail  upon  its  under  surface  is  fash- 
ioned into  thin  vertical  plates,  which  are  received  between  the 
folds  of  the  sensitive  skin.  In  this  manner,  the  two  kinds  of 
laminae  reciprocally  embrace  each  other,  and  the  firmness  of 
connection  of  the  nail  is  maintained.  If  we  look  on  the  sur- 
face of  the  nail,  we  see  an  indication  of  this  structure  in  the 
alternate  red  and  white  lines  which  are  there  observed.  The 
former  of  these  correspond  with  the  sensitive  laminae  ;  the  lat- 
ter with  the  horny  plates.  The  ribbed  appearance  of  the  nail 
is  due  to  the  same  circumstance.  These  sensitive  laminae  are 
provided  with  an  unusual  number  of  capillary  vessels  for  the 
formation  of  the  nail,  and  hence  they  give  a  red  tint  to  the 
portion  under  which  they  lie. 

2d.  Near  the  root  of  the  nail  there  is  a  part  that  is  not 
laminated,  and  it  is  less  abundantly  supplied  with  blood-vessels. 
This  portion  consequently  looks  pale  compared  with  the  lam- 
inated portion,  and  from  its  half-moon  shape  is  technically 
termed  lunula.  Beyond  the  lunula,  the  root  of  the  nail  is 
imbedded  in  the  fold  of  the  sensitive  skin,  and  has  the  same 
relation  to  that  structure  that  any  single  one  of  the  thin  horny 
plates  of  its  under  surface  has  to  its  corresponding  pair  of  sen- 
sitive laminae. 

724.  The  nails,  from  their  position,  are  continually  receiv- 
ing  knocks,  which  produce  a  momentary  disturbance  of  their 
cell  formation,  followed  by  a  white  spot.  The  care  of  the 
nails  should  be  strictly  limited  to  the  knife  or  scissors,  to 

Give  observation  1st.  Observation  2d.  724.  How  should  the  nails  be 
treated  to  prevent  irregularities  and  disease  ? 

28 


3'2G  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

their  free  border,  and  an  ivory  presser,  to  prevent  adhesion 
of  the  free  margin  of  the  scarf-skin  to  the  surface  of  the 
nail.  This  edge  of  the  cuticle  should  never  be  pared,  the 
surface  of  the  nail  never  scraped,  nor  the  nails  cleaned  with 
any  instrument  whatever,  except  the  nail-brush,  aided  by 
water  and  soap.  An  observance  of  these  suggestions,  will 
prevent  irregularities  and  disorders  of  the  nails. 

Observations.  1st.  When  we  wear  a  shoe  that  is  too  short 
for  the  foot,  the  edge  of  the  nail  is  brought  against  the  leather. 
This  interrupts  the  forward  growth  of  the  nail,  and  it  spreads 
out  on  the  sides,  and  becomes  unusually  thick.  It  then  presses 
upon  the  soft  parts,  and  is  said  to  "  grow  into  the  flesh."  The 
prevention  is,  to  wear  shoes  of  ample  size. 

2d.  Instances  are  by  no  means  unfrequent  in  which  the 
power  of  production  of  the  nail  at  the  root  becomes  entirely 
destroyed,  and  it  then  grows  in  thickness  only.  When  this 
affection  occurs,  it  is  often  remarkable  what  a  mass  the  nail 
presents.  Instances  are  on  record,  where  the  nail  is  regularly 
shed  ;  and,  whenever  the  old  nail  falls  off,  a  new  one  is  founa 
beneath  it,  perfectly  formed.  Sometimes  the  growth  in  length 
is  not 'entirely  checked,  although  growth  in  thickness  is  in 
duced  ;  the  nail  then  presents  a  peculiar  appearance. 


What  causes  the  edge  of  the  nail  "  to  grow  into  the  flesh  "  of  the  toe 
How  presented? 


ANATOMY    OF    THE    NERVOUS    SYSTEM. 


CHAPTER     XXXVi 

THE    NERVOUS    SYSTEM. 

725.  IN  the  preceding  chapters,  we  have  seen  how  vnrxas 
and  complex  are  many  of  the  motions  necessary  to  maintain 
the  life  of  an  animal    whose  organization  is  superior  to  all 
others.     We    have   noted   the  wonderful   mechanism   of  the 
muscular  system,  in  producing  the  varied  movements  of  the 
body,  the  different  processes  by  which  the  food  is  converted 
into  chyle  and  mixed  with  the  blood,  and  the  circulation  of 
this  fluid. to  every  organ  and  tissue  of  the  system,  that  each 
may  select  from  it  the  very  principles  which  it  requires  for 
its  growth. 

726.  Lymphatic  absorption  commences  as  soon  as  nutri- 
tion is  completed,  and  conveys  the  useless,  worn-out  particles 
of  different  tissues  back  into  the  circulating  fluid  ;  while  the 
respiratory  organs  and  secretory  glands   perform  the  work 
of  preparing  the  waste  products  to  be   eliminated  from  the 
body.     Each  of  these  processes  effects  a  single  object,  and  is 
performed  in  a  regular  manner. 

727.  "  They  must  succeed  each  other  in  proper  order  in 
propelling  every  particle   to   its   proper   destination,  or  life 
would  be  sacrificed  almost  at  the  moment  of  its  commence- 
ment.   There  is,  therefore,  a  mutual  dependence  of  all  portions 
of  the  machinery  of  organic  life  upon  each  other,  and  a  neces- 
sity for  some   medium  of  communication  from  one  organ  to 
another,  by  which  they  may  convey  mutual  information  of 

725.  What  has  been  noted  in  the  preceding  chapters  ?  726.  Show  tho 
manner  in  which  the  several  processes  are  performed.  727.  How  must 
they  succeed  each  other  ? 


3.  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

their  several,  cjaadiiions,  if  we  may  be  permitted  to  employ  a 
figurative  expression.  Were  there  no  such  medium,  how 
would  the  stomach  notify  the  heart  that  additional  exertion  OR 
its  part  is  required,  because  the  stomach  is  busy  in  digesting 
food  ? 

728.  "  When  we  are  exerting  the  muscular  system  for  a 
long  time  in  some  laborious  employment,  how  else  are  our 
members  to  inform  the  stomach  that  they  are  too  much  occu 
pied  with  their  duties  to  spare  the  blood  necessary  in  diges- 
tion ;  that  it  is  requisite  that  the  appetite  should  decline ;  and 
that  digestion  should  cease  for  the  time,  even  if  the  stomach 
should  be  oppressed  with  its  contents  ?     When  we  are  think- 
ing, how  else  are  the  blood-vessels  to  be  told  that  an  unusual 
supply  of  their  contents  is  wanting  in  the  head  ?  or  when  the 
whole  frame  is  weary  with  exertion,  how,  without  some  regular 
line  of  intelligence  between  all  the  organs,  is  the  brain  to  be 
instructed  that   circumstances   require   that   it   should  go   to 
sleep  ?     To  supply  the  necessary  medium    of    communica- 
tion, Providence  has  furnished  all  the  animals  that  possess 
distinct  organs,  with  a  peculiar  apparatus  called  the  Nervous 
System." 

ANATOMY   OF  THE  NERVOUS  SYSTEM. 

729.  The  NERVOUS  SYSTEM  consists  of  the  Cer'e-lro-spi'nal 
Cen'tre,  and  of  numerous  rounded  and  flattened  white  cords, 
called  nerves,  which  are  connected  at  one  extremity  with  the 
cerebro-spinal  centre,  and  at  the  other,  distributed  to  all  the 
textures  of  the  body.     The  sympathetic  nerve  is  an  exception 
to  this  description  ;   for,  instead  of  one,  it  has   many  small 
centres,  which  are  called  gan'gU-a,  and  which  communicate 
very   freely  with   the    cerebro-spinal    centre,    and   with   its 
nerves. 

728.  What  is  the  medium  of  communication  from  one  organ  to  another  ? 
7^'J — 7^4.  Give  the  anatomy  of  the  brain  and  cranial  nerves.  729L  Of  v.-int 
does  the  nervous  system  consist  ?  What  constitutes  an  exception  to  ius: 


ANATOMY    OF    THE    NERVOflfcv«fk?EM.  329 

730.  The  CEREBRO-SPINAL  CENTRE 

The  brain,  and  the  spinal  cord.  For  convenience  of  de- 
scription, the  nervous  system  may  be  divided  into  the  Brain, 
Cranial  Nerves,  Spinal  Cord,  Spinal  Nerves,  and  the  Sym- 
pathetic Nerve. 

731.  The  term  BRAIN  designates  those  parts  of  the  nervous 
system,  exclusive   of  the  nerves  themselves,  which  are  con- 
tained within  the  cranium,  or  skull-bones ;  they  are  the  Cer'e- 
brum,  Cer-e-bel'lum,  and  Me-dul'la  Ob-lon-ga'ta.     These  are 
invested  and  protected  by  the  membranes  of  the  brain,  which 
are  called  the  Du'ra  Ma'ter,  A-rach'noid,  and  Pi'a  Ma'ter. 


Fig.  120. 


Fig.  120.  1,  1,  The  scalp  turned  down.  2,  2,  2,  The  cut  edge  of  the  bones  of  the 
skull.  3,  The  external  strong  membrane  of  the  hrain  (dura  mater,)  suspended  hy  a 
hook.  4,  The  left  hemisphere  of  the  brain,  showing  its  convolutions. 

730.  Of  what  does  the  cerebro-spinal  centre  consist  ?   How  is  the  nervouo 
system  divided  ?     731.  What  does  the  term  brain  designate  ?     Name  them 
How  are  they  protected  ?     Describe  fig.  120. 
28* 


3JJO 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


732.  The  CEREBRUM  is  divided  into  two  hemispheres,  by  a 
cleft,  or  fissure.  Into  this  cleft  dips  a  portion  of  the  dura 
mater,  called  the  falx  cer'e-bri,  from  its  resembling  a  sickle. 
The  apparent  design  of  this  membrane  is  to  relieve  the  one 
side  from  the  pressure  of  the  other,  when  the  head  is  reclin- 
ing to  either  side.  Upon  the  superior  surface  of  the  cere- 
jrum  are  seen  undulating  windings,  called  con-vo-lu'tions, 
Upon  its  inferior,  or  lower  surface,  each  hemisphere  admits 
of  a  division  into  three  lobes  —  the  anterior,  middle,  and 
posterior,  (Fig.  122,  123.) 

Fig.  121. 


Fig.  121      A  section  of  the  skull-bones  and  cerebrum.     1,  1,  The  skull.  2,  a,  Ihe 

dura  matet      3,  3,  The  cineritious  portion  of  the  cerebrum.     4,  4,   The  medullary 

portion      The  dark  points  indicate  the  position  of  divided  blood-vessels.  5,  5,  The 
lateral  ventricles. 


732.   How  is  the  cerebrum  divided  ?     What  is  the  use  of  the  falx  cerebrif 
What  is  seen  upon  the  superior  surface  of  the  brain  ?    Its  inferior  ? 


ANATOMY    OF    THE    NERVOUS    SYSTEM.  331 

733.  When  the  upper  part  of  the  hemispheres  is  removed 
horizontally  with  a  sharp  knife,  a  centre  of  white  substance  is 
brought  to  view.     This   is  surrounded   by  a  border  of  gray, 
which   follows  the   depressions  of  the  convolutions,  and  pre- 
sents a  zigzag  outline.     The    divided   surface  will  be  seen 
studded  with  numerous  small  red  points,  which  are  produced 
by  the  escape  of  blood  from  the  division  o^the  minute  arte- 
ries and  veins.     The  gray  border  is  called  the  cortical,  or  cin- 
eritious  portion,  while  the  white  central  portion  is  called  the 
medullary.     The  two  hemispheres  are  connected  by  a  dense 

r.yer  of  transverse  fibres,  called  cor'pus  cal-lo'sum. 

734.  In  the  interior  of  the  brain  there  are  several  cavities, 
two  of  which  are  of  considerable  size,   and  are   called  the 
lateral  ventricles.     They  extend  from  the  anterior  to  the  pos- 
terior part  of  the  brain,  and  wind  their  way  into  other  parts  of 
the  cerebral  organ. 

Observation.  In  the  disease  called  "  dropsy  of  the  brain," 
(hydrocephalus  internus,)  the  serum,  or  water,  is  usually  de- 
posited in  these  ventricles.  This  is  effused  from  the  many 
small  blood-vessels  of  the  membrane  in  these  cavities. 

735.  The   brain    is  of   a    pulpy  character,  quite    soft    in 
infancy  and  childhood ;  but  it  gradually  becomes   more  and 
more  consistent,  and  in  middle  age  it  assumes  the  form  of 
determinate   structure    and    arrangement.     It  is  more   abun- 
dantly supplied  with  blood  than  any  organ  of  the  system. 
No  lymphatics  have   been  detected,  but  it  is  to  be  presumed 
that  they  exist  in  this  organ. 

736.  The  CEREBELLUM  is  about  seven  times  smaller  than 
the  cerebrum.     Like  that  organ,  it  is  composed  of  white  and 

733  Describe  the  appearance  of  the  brain  when  a  horizontal  section  has 
been  made.  What  is  the  gray  border  often  called  ?  What  connects  the 
hemispheres  ?  734.  Describe  the  ventricles  of  the  brain.  In  the  disease 
culled  "  dropsy  of  the  brain,"  where  is  the  water  deposited  ?  735.  What 
is  the  character  of  the  brain  in  childhood  ?  In  adults  ?  736.  How  does 
the  cerebellum  compare  in  size  with  the  cerebrum  ? 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE 

gray  matter,  but  the  gray  constitutes  the  larger  portion.  Its 
surt'ace  is  formed  of  parallel  plates  separated  by  fissures. 
The  white  matter  is  so  arranged,  that  when  cut  vertically,  the 
appearance  of  the  trunk  and  branches  of  a  tree  (ar'bor  vi'tcK) 
is  presented.  It  is  situated  under  the  posterior  lobe  of  the 
cerebrum,  from  which  it  is  separated  by  a  process  of  the  dura 
mater,  called  the  ten-to'ri-wn. 

Fig.  122. 


Fig.  122.  The  undei  surface,  or  base,  of  the  brain  and  origin  of  the  G>imial  nerve* 
1,  1,  The  anterior  lobes  of  the  cerebrum.  2,  2,  Th"  middle  lobes.  3,  u,  The  poste 
rior  lobes,  almost  concealed  by  the  cerebellum.  4, 0,  The  cerebellum.  7,  7,  The 
longitudinal  fissure  that  divides  the  brain  into  two  hemispheres.  8,  The  first  pair 
of  nerves.  9.  9,  The  second  pair  of  nerves.  10,  The  decussation,  or  crossing,  of  its 
fibres.  13,  13,  The  third  pair  of  nerves.  14,  The  pons  varolii.  15,  15,  The  fourth 
pair  of  nerves.  16,  16,  The  fifth  pair  of  nerves.  17,  The  sixth  pair  of  nerves. 
18,  18,  The  seventh  and  eighth  pair  of  nerves.  19,  The  medulla  oblongata,  with  the 
crossing  of  some  of  its  fibres  exhibited.  20,  The  ninth  pair  of  nerves.  21,  The  tenth 
pair  of  nerves.  22,  The  eleventh  pair  of  nerves.  23,  The  twelfth  pair  of  nerves. 


Describe  this  portion  of  the  brain.     Explain  fig.  122. 


ANATOMY    OF    THE    NERVOUS    SVSTEM. 


333 


737.  The  MEDULLA  OBLONGATA,  or  that  portion  of  the 
spinal  cord  which  is  within  the  skull,  consists  of  three  pairs 
of  bodies,  (cor'pus  py-ram-i-da'le,  res-ti-for'me^ and  ol-i-vare,) 

united  in  a  single  bulb. 

Fig.  123. 


Fig.  123.  The  base  of  tte  skull  and  the  openings  through  which  the  cranial  nerve* 
pass.  1,  1,  The  first  pau  «f  Merves.  2,  2,  The  cribriform  plate  of  the  ethmoid  bone, 
through  which  this  nerve  pas»es.  3,  3,  The  second  pair  of  nerves.  4,  4,  The  optic 
foramen  in  the  sphenoid  bone  5  through  which  passes  the  second  pair  of  nerves 
5,  5,  The  sphenoidal  fissure.  6,  6,  The  third  pair  of  nerves.  7,  7,  The  fifth  pair  of 
nervea  8,8,  The  ophthalmic  branch  of  the  fifth  nerve.  The  third,  the  ophthalmic 
branch  of  the  fifth  and  the  sixth  nerve  pass  from  the  brain  through  the  sphenoids) 
fissure  to  the  eye.  9, 9,  The  superior  maxillary  branch  of  the  fifth  nerve.  1(T,  10,  The 
fo-amen  rotundum,  (round  opening,)  through  which  the  nerve  9,9,  passes  to  the  upper 
jaw.  11,  11,  The  inferior  maxillary  branch  of  the  fifth  pair.  12,  12,  The  foramen 
ovale,  (oval  opening,)  through  which  the  nerve  11,  11,  passes  to  the  lower  jaw. 
13, 13,  The  sixth  pair  of  nerves.  14,  14,  The  seventh  and  eighth  pair  of  nerves. 
15,  15,  The  opening  in  the  temporal  bone,  through  which  the  seventh  and  eighth 
nerves  pass  to  the  face  and  ear.  16,  16,  The  ninth  pair  of  nerves.  17,  The  tenth 
pair  of  nerves.  18,  18,  The  eleventh  pair  of  nerves.  19,  19,  The  foramen  lacerum 
(rough  opening.)  The  ninth,  tenth,  and  eleventh  nerves  pass  from  the  brain  through 
this  opening.  20,  The  spinal  cord.  21,  The  foramen  spinalis,  through  which  the 
spinal  cord  passes.  22,  22,  The  position  of  the  anterior  lobe  of  the  brain.  23, 23,  The 
middle  lobe.  24,  24,  The  posterior  lobe.  25, 25,  A  section  of  the  skull-bones. 


737.  Describe  the  medulla  oblongata.     Explain  fig.  123. 


334 


ANATOMY,    PHYSIOLOGY.    AND    HYGIENE. 


738.  The  DURA  MATER  is  a  firm,  fibrous  membrane,  which 
is  exposed  on  the  removal  of  a  section  of  the  skull-bones. 
This  lines  the  interior  of  the  skull  and  spinal  column,  and 
likewise  sends  processes  inward,  for  the  support  and  protec 
lion  of  the  different  parts  of  the  brain.  It  also  sends  pro- 
cesses externally,  which  form  the  sheaths  for  the  nerves,  as 
they  quit  the  skull  and  spinal  column.  The  dura  mater  is 
supplied  with  arteries  and  nerves. 

Fig.  124. 


Fig.  124.  A  vertical  section  of  the  cerebrum,  cerebellum,  and  medulla  oblongkta- 
showing  the  relation  of  the  cranial  nerves  at  their  origin.  1,  The  cerebrum.  2,  Tho 
cerebellum,  with  its  arbor  vitoe  represented.  3,  The  medulla  oblongata.  4,  The  spinal 
cord.  5,  The  corpus  callosum.  6,  The  first  pair  of  nerves.  7,  The  second  pair 
8,  The  eye.  9,  The  third  pair  of  nerves.  10,  The  fourth  pair.  11,  Tb«>  fifth  pair. 
12,  The  sixth  pair.  13,  The  seventh  pair.  14,  The  eighth  pair.  15,  Tho  flinth  pail. 
16,  The  tenth  pair.  19,  The  eleventh  pair.  18,  The  twelfth  pair.  90,  Spinal 
nerves.  21,  The  tentorium. 


738.  Describe  the  dura  mater.     What  is  its  use  ?     Explair  fig   124. 


ANATOMY    OF    THE    NERVOUS    SYSTEM.  ,'j35 

739.  The  ARACHNOID,  so  called  from  its  extreme  tenuity,  is 
the  serous  membrane  of  the  brain  and  spinal  cord,  and  is,  like 
other  serous  membranes,  a  closed    sac.     It   envelops  these 
organs,  and  is  reflected  upon  the   inner  surface  of  the  dura 
mater,  giving  to  that  membrane  its  serous  investment. 

740.  The  PIA   MATER  is  a  vascular  membrane,  composed 
of  innumerable  vessels,  held  together  by  cellular  membrane. 
It  invests  the  whole   surface  of  the   brain,  and   dips  into  its 
convolutions.     The  pia  mater  is  the  nutrient  membrane  of  the 
brain,  and  receives  its  blood  from  the  carotid  and  vertebral 
arteries.     Its  nerves  are  minute  branches  of  the  sympathetic, 
which  accompany  the  branches  of  the  arteries. 

741.  The  CRANIAL  NERVES,  that  connect  with  the  brain,  are 
arranged  in  twelve   pairs.     They  are   called  :   1st.    The   Ol- 
fact'o-ry.     2d.  The  Op'tic.     3d.  The  Mo-to'res  Oc-u-lo'rum. 
4th.   The    Pa-thet'i-cus.      5th.   The    Tri-fa'cial.      6th.   The 
Ab-du-cerites.     7th.   The  Por'ti-o  Du'ra.     8th.   The  Por'ti-o 
Mol'lis.     9th.   The  Glos'so-pha-ryn'gi-al.      10th.    The  Pneu- 
mo-gas1  trie.      llth.    The    Spi'nal   Ac'ces-so-ry.      12th.    The 
Hy'po-glos'sal. 

742.  The   OLFACTORY  NERVE  (first  pair)  passes  from  the 
cavity  of  the  skull  through  many  small  openings  in  a  plate  of 
the  etli'moid  bone.     (This  plate  is  called  crib'ri-form,  from 
its  resemblance  to  a  sieve.)     This  nerve  ramifies  upon  the 
membrane  that  lines  the  nasal    passages.     It  is  the  softest 
nerve  of  the  body.     (Fig.  136.) 

743.  The  OPTIC  NERVE  (second  pair)  passes  from  the  inte- 
rior of  the  cranium,  through  an  opening  in  the  base  of  the 
skull,  (fo-ra'men  op'ti-cum,)  to  the    cavity  for  the   eye.     It 
pierces  the  coats  of  the  eye,  and  expands  in  the  retina. 

744.  The  MOTORES  OCULORUM  (third  pair)   pass  from  the 

739.  Describe  the  arachnoid  membrane.  740.  What  is  said  respecting 
the  pia  mater  ?  741.  How  many  pairs  of  cranial  nerves  ?  Name  them. 
742.  Describe  the  olfactory  nerve.  743.  The  optic  nerve.  744  Describe  the 
motores  oculorum. 


336  ANATOMV,    PHYSIOLOGY,    AND    HYGIENE. 

brain,  through  an  opening  of  the  sphe'noid  bone,  (splie-noid1  a* 
fis'sure,)  to  the  muscles  of  the  eye. 

745.  The  PATHETICUS  (fourth  pair)  passes  from  the  brain, 
through  the  sphenoidal  fissure,  to  the  superior  oblique  muscle 
of  the  eye. 

Fig.  125. 


Pig.  125.  The  distribution  of  the  third,  fourth,  and  sixth  pairs  of  nerves,  to  tho 
muscles  of  the  eye.  1,  The  ball  of  the  eye  and  rectus  externus  muscle.  2,  The  up 
per  jaw.  3,  The  third  pair,  distributed  to  all  the  muscles  of  the  eye,  except  the 
superior  oblique,  and  external  rectus.  4,  The  fourth  pair  passes  to  the  superior 
oblique  muscle.  6,  The  sixth  pair,  is  distributed  to  the  external  rectus  muscle. 

746.  The  TRIFACIAL  NERVE  (fifth  pair)  is  analogous  to  the 
spinal  nerves  in  its  origin  by  two  roots,  from  the  anterior 
and  posterior  columns  of  the  spinal  cord.  It  has  a  ganglion, 
like  the  spinal  nerves  upon  its  posterior  root.  For  these 
reasons,  it  ranges  with  the  spinal  nerves,  and  is  considered 
the  cranial  spinal  nerve.  This  nerve  divides  into  three 
branches  :  —  The  oph-thal'mic,  superior  max'il-la-ry,  and  in- 
ferior max'il'la-ry. 

745.  The  patheticua.  What  does  fig.  125  represent  ?  746.  What  is  the 
trifacial  nerve  sometimes  called  ?  Why  is  it  classed  with  the  cranial 
spinal  nerves  ?  Giv«  the  names  of  its  branches. 


ANATOMY  OF  THE  NERVOUS  SYSTEM.         337 

*747.  The  ophthalmic  nerve  passes  from  the  cranial  cavity 
through  the  sphenoidal  fissure.  It  sends  branches  to  the  fore- 
head, eye,  and  nose.  The  superior  maxillary  nerve  passes 
through  an  opening  in  the  base  of  the  skull,  (foramen  ro-tun'- 
dum,)  and  sends  branches  to  the  eye,  the  teeth  of  the  upper 
jaw,  and  the  muscles  of  the  face.  The  inferior  maxillary  nerve 
escapes  from  the  cranial  cavity  through  an  opening  called 
foramen  o-va'le.  It  sends  branches  to  the  muscles  of  the 
lower  jaw,  the  ear,  the  tongue,  and  the  teeth  of  the  lower  jaw. 

Fig.   126. 


Pig.  126.    The  distribution  of  the  fifth  pair  of  nerves.     1,  The  orbit  for  the  eye. 

5,  The  upper  jaw.    3,  The  tongue.    4.  The  lower  jaw.    5,  The  fifth  pair  of  nerves. 

6,  The  first  branch  of  this  nerve,  that  passes  to  the  eye.      9,    10,  11,  12,  13,  14, 
Divisions  of  this  branch.    7,  The  second  branch  of  the  fifth  pair  of  nerves  is  dis- 
tributed   to  the  teeth   of  the  upper  jaw.      15,  16,  17,  18,  19,  20,  Divisions  of  Urn 
branch.    8,  The  third  branch  of  the  fifth  pair,  that  passes  to  the  tongue  and  teeth  of 
the  lower  jaw.    23.  The  division  of  this  branch  that  passes  to  the  tongue,  called  the 
gust'a-to-ry.    24.  The  division  that  is  distributed  to  the  teeth  of  the  lower  jaw. 

747.   Where  do  the  filaments  of  the  ophthalmic  branch  ramify  ?     The 
superior  maxillary  ?    The  inferior  maxillary  ?    Explain  fig.  126. 

29 


338  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

748.  The  ABDUCENTES  (sixth  pair)  passes  through  the  tj>en« 
ing  by  which    the  carotid  artery  enters  the  cranial   cavity, 
It  is  the  smallest  of  the  cerebral  nerves,  and  is  appropriated 
to  the  external  straight  muscle  of  the  eye. 

749.  The  PORTIO    MOLLIS  (seventh  pair)  enters  the  hard 
portion  of  the  iem'po-ral  bone  at  the  internal  auditory  open- 
ing, and  is  distributed  upon  the  internal  ear.    (Fig.  147,  148.) 

Fig.  127. 


Kig.  127.  A  representation  of  the  distribution  of  the  eighth  pair  of  nerves  wit* 
y»ne  branches  of  the  fifth.  1,  2,  3,  5,  7,  9,  Are  branches  of  the  eighth  pair.  They 
are  distributed  over  the  face  in  a  radiated  manner,  which  constitutes  the  pea  an- 
serinus,  (foot  of  a  goose.)  The  nerves  4,  6,  8,  are  branches  of  the  fifth  pair.  10, 
11,  12,  13,  14,  15,  16,  Are  branches  of  nerves  from  the  upper  part  of  the  spinal  cord, 
(cervical.) 

750.  The  FACIAL  NERVE  (eighth  pair)  passes  from  the  skull 
through  an  opening  situated  below  the  ear,  (mas'toid  fora- 
men.) It  is  distributed  over  the  face,  supplying  the  muscles 
with  nervous  filaments. 

748.  What  is  said  of  the  abducentes,  or  sixth  pair  of  nerves  ?  749.  Of 
the  portio  mollis  ?  Explain  fig.  127.  750.  Of  the  facial  nerve  ? 


ANATOMY    OF    THE    NEKVOUS    SYSTEM.  339 

751.  The  GLOSSO-PHARYNGEAL  NERVE  (ninth  pair)  passes 
from  the  brain,  through  an  opening  with  the  jugular  vein,  (fo- 
ramen lac'e-rum.)     It  is  distributed  to  the  mucous  membrane 
of  the  tongue  and  throat,  and  also  to  the  mucous  glands  of 
the  mouth. 

752.  The  PNETJMOGASTRIC  NERVE  (tenth  pair)  escapes  from 
the  brain  through  the  foramen  lacerum.     It  sends  branches 
to  the  larynx,  pharynx,   oesophagus,  lungs,  spleen,  pancreas 
liver,  stomach,  and  intestines.     (Fig.  132.) 

753.  The  SPINAL  ACCESSORY  NERVE  (eleventh  pair)  has  its 
origin  in  the  respiratory  tract  of  the  spinal  cord.     It  connects 
with  the  ninth  and  tenth  pairs  of  nerves,  and  is  distributed  to 
the  muscles  about  the  neck. 

754.  The  HYPO-GLOSSAL  NERVE  (twelfth  pair)  passes  from 
the  brain,  through  a  small  opening,  (con 'dy-loid  foramen.)     It 
ramifies  upon  the  muscles  of  the  tongue,  and  is  its  motor 
nerve. 

Observation.  The  cranial  nerves,  with  the  exception  of  the 
olfactory,  optic,  and  auditory,  connect  with  each  other  by 
means  of  filaments.  They  also  send  connecting  nervous  fila- 
ments to  the  upper  spinal  nerves,  (cervical,)  and  the  sympa- 
thetic nerve. 


751.    Describe  the  glosso-pharyngeal  nerve      752.  The  pneumogas*  ' 
nerve.    753   The  spinal  accessory  nerve.     754.  Th<  byjv  -/»?oiH7s?  nrrre. 


310  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

CHAPTER    XXXVII. 

ANATOMY    OF    THE    NERVOUS    SYSTEM,    CONTINUED. 

755.  THE  spinal  column  contains  the  spinal  cord,  the  roots 
of  the  spinal  nerves,  and  the  membranes  of  the  cord. 

756.  The  SPINAL  CORD  extends  from  the  medulla  oblongata 
/o  the  second  lumbar  vertebra,  where  it  terminates  in  a  round- 
ed  point.     It  presents  a  difference  of  diameter   ki  different 
parts  of  its  extent,  and  exhibits  three   enlargements.      The 
uppermost  of  these  is  the  medulla  oblongata.     There  is  no 
distinct  demarkation  between  this  enlargement  and  the  spinal 
cord.     The  next  corresponds  with  the  origin  of  the  nerves 
distributed  to  the  upper  extremities  ;  the   third   enlargement 
is  situated  near  the  termination  of  the  cord,  and  corresponds 
with  the  attachment  of  the  nerves  which  are  intended  for  the 
supply  of  the  lower  extremities. 

757.  An  anterior  and  posterior  fissure   divides  the  spinal 
cord  into  two  lateral  cords.     These  are  united  by  a  thin  layer 
of  white  substance.     The   lateral  cords  are  each  divided  by 
furrows  into  three  distinct  sets  of  fibres,  or  columns ;  namely 
the  anterior,  lateral,  and  posterior  columns.     The  anterior 
are  the  motor  columns  ;  the  posterior  are  the  columns  of  sen- 
sation ;  the  lateral  columns  are  divided  in  their  function  be- 
tween  motion  and  sensation.      They  contain  the  fasciculus 
described,  by  Sir  Charles  Bell,  as  the  respiratory  tract. 

755—767.  Give  the  anatomy  of  ike  spinal  cord,  spinal  nerves,  and  the  sym- 
pathetic nerve.  755.  What  does  the  spinal  column  contain  ?  756.  Give  tk 
extent  of  the  spinal  cord.  How  many  enlargements  has  this  cord  ?  "What 
is  said  of  each  enlargement?  757.  Into  how  many  parts  is  the  spinaJ 
30 rd  divided  ?  Give  the  function  of  these  columns. 


ANATOMY    OF    THE    NERVOUS    SYSTEM. 


758.    The  SPINAL  NERVES,  that   connect   with   the    spinal 
cord,  are  arranged  in  thirty-one   pairs,  each  arising  by  two 


Fig.  128. 


Fig.  129. 


14- 


Fig.  128.  A  section  of  the  brain  and  spinal  column.  1,  The  cerebrum.  2  fh« 
cerebellum.  3,  The  medulla  oblongata.  4,  4,  The  spinal  cord  in  its  canal. 

Fig.  129.  Anterior  view  of  the  brain  and  spinal  cord.  1,  1,  The  two  hemispheres 
of  the  cerebrum.  3,  3,  The  cerebellum.  4,  The  olfactory  nerve.  5,  The  optic 
nerve.  7,  The  third  pair  of  nerves.  8,  The  pons  varolii.  9,  The  fourth  pair  of 
nerves.  10,  The  lower  portion  of  the  medulla  oblongata.  11,  11,  The  spinal  cord. 
12,  12,  Spinal  nerves.  13,  13,  The  brachial  plexus.  14,  14,  The  lumbar  and  sacral 
plexus. 


758.  How  many  pairs  of  nerves  issue  from  the  spinal  cord  ?    Explain  fig 
128.    Fig.  129. 

29* 


342 


ANATOMY,    PHYSIOLOGY,    AND     HYGIENE. 


roots  ;  an  anterior,  or  motor  root,  and  a  posterior,  or  sensitive. 
root.  Each  nerve,  when  minutely  examined,  is  found  to  con- 
sist of  an  aggregate  of  very  delicate  filaments,  enclosed  in  a 
common  cellular  envelope. 

759.  The  anterior  roots  arise  from  a  narrow  white  line 
upon  the  anterior  columns  of  the  spinal  cord.  The  posterior 
roots  arise  from  a  narrow  gray  band  formed  by  the  internal 
gray  substance  of  the  cord.  They  are  larger,  and  the  fila- 
ments of  origin  more  numerous  than  those  of  the  anterior 
roots.  A  ganglion  is  found  upon  each  of  the  posterior  roots 
in  the  openings  between  the  bones  of  the  spinal  column  through 
which  the  nerve  passes. 

Fur.  130. 


Fig.  130.  A  section  of  the  spinal  cord,  surrounded  by  its  sheath.  B,  A  spinal 
nerve,  formed  by  the  union  of  the  motor  root  (C)  and  the  sensitive  root  (I).)  At  D, 
the  ganglion  upon  this  root  is  seen. 

760.  After  the  formation  of  the  ganglion,  the  two  roots 
unite,  and  constitute  a  spinal  nerve,  which  passes  through  the 
opening  between  the  vertebra  on  the  sides  of  tho  spinal 
column.  The  nerves  divide  and  subdivide,  until  their  minute 
filaments  ramify  on  the  tissues  of  the  different  organs. 

7;>9.  Oive  the  origin  of  the  anterior  roots.  Of  the  posterior  roots.  In 
wnat  respect  do  the  posterior  roots  differ  from  the  anterior  ?  760.  When 
do  the  two  roots  unite,  and  where  do  '.hey  pass  ? 


ANATOMY    OF    THE    NERVOUS    SYSTEM  343 

761.    The  spinal  nerves  are  divided  into  — 

Cervical, 8  pairs, 

Dorsal, 12     " 

Lumbar,    " 5     " 

Sacral,        .......       6     " 

^W$.  The  four  lower  cervical  and  upper  dorsal  pass  into 
each  oiher  and  then  separate  to  reunite.  This  is  called  the 
brack' i-al  plex'us.  From  this  plexus  six  nerves  proceed, 
which  ramify  upon  the  muscles  and  skin  of  the  upper  ex- 
tremities. 

763.  The  last  dorsal  and  the  five  lumbar  nerves  form  a 
plexus  called  \he  lumbar,  similar  to  that  of  the  cervical.     Six 
nerves  pass  from  this  plexus,  which  ramify  upon  the  muscles 
and  skin  of  the  lower  extremities. 

764.  The  last  lumbar  and  the  four  upper  sacral  unite  to 
form   the  sacral  plexus.     From  this  plexus  five  nerves  pro- 
ceed, that  are  distributed  to  the  muscles  and  skin  of  the  hip 
and  lower  extremities. 

765.  The   SYMPATHETIC  NERVE  *   consists  of  a   series  of 
Gan'gli-a,  or  knots,  extending  each  side  of  the  spinal  column, 
forming  a  chain  its  whole  length.     It  communicates  with  both 
*he  cranial  and  spinal   nerves.     With  the  exception  of  the 
neck,  there  is  a  ganglion  for  each  intervertebral  space.    These 
ganglia  are  composed  of  a  mixture  of  cineritious  and  medul- 
lary matter,  and  are  supposed  to  be  productive  of  peculiar 
nervous  power. 


*  The  structure  of  this  nerve  is  very  complicated,  and  different 
physiologists  ascribe  to  it  various  functions.  The  character  of  its  dis- 
eases are  not  well  understood. 

761.  Give  the  division  of  the  spinal  nervess  762.  What  nerves  consti- 
tute the  brachial  plexus?  How  many  nerves  pass  from  this  plexus? 
763.  How  many  nerves  from  the  lumbar  plexus,  and  where  do  they  ram- 
ify ?  764.  How  is  the  sacral  plexus  formed  ?  765.  Of  what  does  the 
sympathetic  nerve  consist  ?  How  is  the  sympathetic  nerve  distributed  ? 
What  exception  ?  Of  what  are  the  ganglia  composed  ? 


AN  ATOM  r,    PHYSIOLOGY,    ANT>    HYGIENE. 
Fig.    131. 


ANATOMY    OF    THE    NERVOUS    SYSTEM  315 

766.  The  GANGLIA  may  be  considered   as  distinct  centres, 
giving  off  branches  in  four  directions  ;  namely,  the  superior, 
or  ascending,  to  communicate  with   the  ganglion  above  ;  the 
inferior,  or  descending,  to    communicate  with  the  ganglion 
below  ;  the  external,  to  communicate  with  the  spinal  nerves  ; 
and  the  internal,  to  communicate  with  the  sympathetic  fila- 
ments.    It  is  generally  admitted  that  the  nerves  that  pass  from 
the  ganglia  are  larger  than  those  that  entered  them ;  as  if 
they  imparted  to  the  nerve  some  additional  power. 

767.  The  branches  of  distribution  accompany  the  arteries 
which  supply  the  different  organs,  and  form  communications 
around  them,  which  are  called  plexuses,  and  take  the  name 
of  the  artery  with  which  they  are  associated.     Thus  we  have 
the  mesenteric  plexus,  hepatic  plexus,  splenic  plexus,  &c.    All 
the  internal  organs  of  the  head,  neck,  and  trunk,  are  supplied 
with  branches  from  the  sympathetic,  and  some  of  them  exclu- 
sively ;  for  this  reason,  it  is  considered  a  nerve  of  organic  life. 

Fig.  131.  A  beautiful  representation  of  the  sympathetic  ganglia  and  their  connec- 
tion with  other  nerves.  It  is  from  the  grand  engraving  of  Manec,  reduced  in  *i/e. 
A,  A,  A,  The  semilunar  ganglion  and  solar  plexus,  situated  below  the  (iiaphr  IL'MI 
and  behind  the  stomach.  This  ganglion  is  situated  in  the  region  (pit  of  the  stom- 
ach) where  a  blow  gives  severe  suffering.  D,  D,  D,  The  thoracic  ganglia,  ten  or 
eleven  in  number.  E,  E,  The  external  and  internal  branches  of  the  thoracic  jjan- 
glia.  G,  H,  The  right  and  left  coronary  plexus,  situated  upon  the  heart.  I,  N.  Q. 
The  inferior,  middle,  and  superior  cervical  ganglia.  1,  The  renal  plexus  of  nrrves 
that  surrounds  the  kidneys.  2,  The  lumbar  ganglion.  3,  Their  internal  branches. 
4,  Their  external  branches.  5,  The  aortic  plexus  of  nerves  that  lies  upon  the  «'irta. 
The  other  letters  and  figure;  represent  nerves  that  connect  important  organ*  and 
nerves  with  the  sympathetic  ganglia. 

What   is   the  design  of  fig.  131  ?     766.   How  may  the  ganglia  be  c»  usid 
-:red  ?     767.   What  is  said  of  the  branches  ut'  the  sympathetic  nerve? 


346  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

CHAPTER    XXXVIII. 

PHYSIOLOGY    OF    THE    NERVOUS    SYSTEM. 

768.  THE  brain  is  regarded  by  physiologists  and  philoso- 
phers as  the  organ  of  the  mind.     Most  writers  consider  it  as 
an   aggregate  of  parts,  each  charged  with  specific  functions, 
and  that  these  functions  are  the  highest  and  most  important 
in  the  animal  economy.     To  the  large  brain,  or  cerebral  lobes, 
they  ascribe  the  seat  of  the  faculties  of  thinking,  memory,  and 
the  will.     In   man,  this  lobe  extends  so  far  backward  as  to 
cover  the  whole  of  the  cerebellum.     To  the  cerebellum,  or 
little  brain,  is  ascribed  the  seat  of  the  animal,  or  lower  pro- 
pensities. 

769.  "  The   constant  relation  between  mental  power  and 
development  of  brain,  explains  why  capacities  and  dispositions 
are   so  different.     In  infancy,   for  example,  the    intellectual 
powers  are  feeble  and  inactive.     This  arises  partly  from  the 
inaptitude  of  a  still  imperfect  brain  ;  but  in  proportion  as  the 
latter  advances  toward  its   mature  state,  the   mental  faculties 
also  become  vigorous  and  active." 

770.  We   are  able,   in   most   instances,  at  least,  to  trace  a 
correspondence  between  the  development  of  the  cerebral  lobes 
and  the  amount  of  intelligence  possessed  by  the  person.     The 
weight  of  the  brain  in  man  to  that  of  the  whole  body  varies 


768 — 772.  Give  the  physiology  of  the  nervous  system.  768.  How  is  the 
Drain  regarded  by  physiologists  and  philosophers  ?  What  do  they  ascribe 
to  the  cerebrum  ?  To  the  cerebellum  ?  769.  What  does  the  relation  be- 
tween mental  powers  and  development  of  brain  explain?  770.  What  is 
said  respecting  the  correspondence  between  the  development  of  the  brain 
and  .nc  amount  of  intelligence  possessed  by  the  person  ?  What  is  said  of 
t*.e  weight  of  tlie  bruin  ? 


PHYSIOLOGY    OF    THE    NERVOUS    SYSTEM. 

in  different  individuals.     The  heaviest  brain  on  record  was 
that  of  Cuvier,  which  weighed  4  pounds  and  13  1-2  ounces. 

771.  The  brain  likewise  holds  an  important  relation  to  all 
the  other  organs  of  the  system.     To  the  muscular  system  it 
imparts  an   influence  which  induces  contraction  of  the  fibres. 
By  this  relation  they  are  brought  under  the  control  of  the  will. 
To  the  skin,  eye,  and  ear,  it  imparts  an  influence  that  gives 
sensibility,  or  the  power  of  feeling,  seeing,  hearing,  &c. 

772.  Again,  the  involuntary  functions  of  the  different  por 
tions  of  the  system  are  more  or  less  influenced  by  the  brain. 
If  the  action  of  this  central  organ  of  the  nervous  system  ih 
destroyed,  the  functions  of  the  digestive,  respiratory,  and  cir- 
culatory apparatuses  will  be  much  disturbed  or  entirely  sup- 
pressed. 

773.  The  brain  is  the  seat  of  sensation.     It  receives  the 
impressions  made  on  all  parts  of  the  body,  through  the  medium 
of  the  sensitive    nerves.     That  the  impressions  of  external 
objects,  made  on  these  nerves,  be  communicated  to  the  brain, 
where  sensation  is  perceived,  it  is  necessary  that  they  be  not 
diseased  or  injured. 

Observation.  There  is  a  plain  distinction  between  sensa- 
tions and  impressions ;  the  latter  are  the  changes  produced 
in  the  extremities  of  the  nerve ;  the  former,  the  changes  pro- 
duced in  the  brain  and  communicated  to  the  mind. 

774.  What  part  of  the  brain  receives  the  impressions  or  has 
the  most  intimate    relation  with  the   intellectual  faculties  is 
unknown.     Some  portions,  however,  are  of  less  importance 
than  others.     Large  portions  of  the  cortical,  or  outer  part,  are 
frequently  removed  without   affecting   the  functions  of  this 

771.  What  is  said  of  the  relation  of  the  brain  to  all  of  the  organs  of  the 
body  ?  772.  Are  the  involuntary  functions  of  different  parts  of  the  system 
influenced  by  the  brain  ?  773.  Where  is  sensation  perceived  ?  By  what 
agency  are  the  impressions  of  external  objects  conveyed  to  the  brain  ? 
What  is  the  difierence  between  sensations  and  impressions  ?  774.  Is  it 
known  what  part  of  the  brain  has  the  most  intimate  relation  with  the  intel- 
lectual faculties  ? 


'.i  IS  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE, 

organ.  Pieces  of  the  medullary,  or  central  parts,  have  beeu 
removed  by  injuries  without  impairing  the  intellect  or  destroy- 
ing life.  This  organ,  although  it  takes  cognizance  of  every 
sensation,  is,  of  itself,  but  slightly  sensible.  It  may  be  cut,  or 
parts  may  be  removed  without  pain,  and  the  individual,  at 
the  same  time,  retain  his  consciousness. 

775.  The  brain  is  the  seat  of  the  will.     It  superintends  the 
physical  as  well  as  the  mental  movements,  and  the  medium  of 
communication  from  this  organ  to  the  muscles,  or  the  parts  to 
be  moved,  is  the  motor  nerves.     If  the  brain  is  in  a  quies- 
cent state,  the  muscles  are  at  rest ;  if,  by  an  act  of  the  will, 
the  brain  sends  a  portion  of  nervous  influence  to  a  voluntary 
muscle,  it  immediately  contracts,  and  those  parts  to  which  the 
muscle  is  attached  move.     There  is  no  perceptible  interval 
between  the  act  of  the  will  and  the  motion  of  the  part. 

776.  Some  physiologists  assert,  that  the  medulla  oblongata 
is  the  point  at  which  excitement  to  motion  commences,  and 
sensation  terminates ;  and  also,  that  it  possesses  the  power  of 
originating  motion  in  itself. 

Observation.  The  medulla  oblongata,  unlike  the  brain,  is 
highly  sensitive  ;  if  slightly  punctured,  convulsions  follow  ;  if 
much  injured,  respiration,  or  breathing,  immediately  ceases. 

777.  It  is  remarkable  that  the  nerves  which  arise  from 
the   right  side  of  the  spinal  cord  communicate  with  the  left 
hemisphere  of  the  cerebrum,  and  vice  versa ;  this  results  from 
the  crossing  of  the  fibres  in  the  medulla  oblongata.     It  follows 
from  this,  that  if  the  right  side  of  the  brain  receives  an  injury, 
the  parts  of  the  opposite  side  of  the  body  lose  their  sensibility 
and  motion. 

Observations.  1st.  If  the  cranial  nerves  which  are  connected 


"What  portions  have  been  removed  without  impairing  the  intellect  ? 
What  is  remarkable  of  the  brain  ?  775.  What  is  the  influence  of  the  brain 
upon  the  muscles  ?  776.  What  do  some  physiologists  assert  of  the  medul- 
la oblongata?  777-  What  is  remarkable  o\  *.he  nerves?  Give  the  Isl 
observation  relative  to  the  cranial  nerves. 


PHYSIOLOGY    OF    THE    NERVOUS    SYSTEM. 

by  a  single  root  are  divided,  only  the  sensation  of  the  .part 
to  which  they  are  distributed  is  lost.  Thus,  if  the  optic  nerve 
is  divided,  the  sense  of  vision  disappears,  but  the  motions  of 
the  eye  are  performed  as  readily  as  before.  But,  if  the  spinal 
nerves  are  divided,  both  sensation  and  motion  of  the  part  to 
which  they  lead  are  destroyed. 

2d.  When  the  spinal  cord  is  divided  or  compressed,  as  in 
fractures  of  the  spinal  column,  all  parts  below  the  fracture  are 
paralyzed,  though  the  nerves  leading  to  these  parts  may  be 
uninjured. 

3d.  Again,  one  side  of  the  body  or  one  limb  may  become 
insensible,  and  the  power  to  move  it,  be  perfectly  retained  ;  or 
the  reverse  of  this  may  happen  —  the  power  of  motion  will 
be  lost  while  sensation  remains.  In  the  former  instance,  the 
function  of  the  posterior,  or  sensitive  column  of  the  spinal  cord 
on  one  side  is  destroyed  ;  in  the  latter,  the  anterior,  or  motoi 
column  is  affected. 

4th.  In  some  cases,  both  sensation  and  motion  of  one  side 
of  the  body  or  one  limb  are  destroyed.  In  such  instances, 
both  the  anterior  and  the  posterior  columns  of  one  side  of 
the  spinal  cord  are  diseased. 

778.  Vigorous  and  controllable  muscular  contraction  re- 
quires a  sound  and  well-developed  brain.  If  this  organ  is 
defective  in  these  particulars,  the  movements  will  be  ineffi- 
cient, and  may  be  irregular.  The  central  organ  of  the  ner- 
vous system  must,  likewise,  be  in  an  active  condition,  to  induce 
regular,  steady,  and  controllable  muscular  movements. 

Observations.  1st.  Persons  who  have  suffered  from  apo- 
plexy and  other  severe  diseases  of  the  brain,  have  an  involun- 
tary trembling  of  the  limbs,  which  results  from  a  weakened 
state  of  the  nervous  system. 

To  the  spinal  nerves.  What  is  said  of  the  compression  of  the  spinal 
cord  ?  Give  the  3d  observation  relative  to  the  spinal  nerves.  The  4th 
observation.  778.  Upon  what  does  vigorous  controllable  muscular  con- 
traction depend  ?  What  causes  the  involuntary  trembling  of  the  limbs 
.11  persons  who  have  suffered  from  apoplexy  ? 

30 


350  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

2d.  The  tremor  of  the  hand,  that  lessens  the  usefulness  01 
incapacitates  the  fine  artist  or  skilful  mechanic,  in  the  prime 
of  life,  from  pursuing  their  vocations,  may  be,  and  is  often, 
induced  by  the  influence  of  intoxicating  drink,  which  debili- 
tates and  disorganizes  the  brain. 

3d.  The  tottering  step,  trembling  hand,  and  shaking  head 
of  the  aged  invalid,  are  the  results  of  diminished  nervous 
energy,  so  that  steady  muscular  contraction,  so  essential  to 
regular  movements,  cannot  be  maintained. 

779.  No  difference  can  be  discovered  in  the  structure  of 
the  several  kinds  of  nerves  in  any  part  of  their  course,  and 
the  functions  they  are  designed  to  perform  can  only  be  known 
by  ascertaining  the  place  of  their  origin.     The  nerves  may 
be  functionally  divided  into  five  groups. 

780.  1st.  Nerves  of  special  sensation.     These  are  the  first, 
second,  eighth,  and  it  may  be  one  of  the  branches  of  the  fifth 
pair  of  cranial  nerves.     The  function  of  these  nerves  is  par- 
ticularly described   in  the  chapters  upon  the  senses  of  smell, 
vision,  hearing,  and  taste. 

781.  2d.  Nerves  of  general  sensation.     These  embrace  the 
fifth   pair  of  cranial  nerves,  and  the  thirty-one  pairs  of  spinal 
nerves.     In  those  parts  that  require  sensation  for  their  safety 
and  the  performance  of  their  functions,  there  is  an  abundant 
supply  of  sensitive  nervous  filaments.     The  nerves  of  sensa- 
tion  are  mostly  distributed    upon  the   skin.     Few  filaments 
ramify  upon  the  mucous  membranes  and  muscles. 

Observations.  1st.  The  painful  sensations  experienced  in 
the  face,  and  in  the  teeth  or  jaws,  (tic  douloureux  and  tooth- 
ache,) are  induced  by  irritation  and  disease  of  a  portion  of 
the  filaments  of  the  fifth  pair  of  cranial  nerves. 


The  tremor  of  the  hand  among  some  mechanics  in  the  prime  of  life  ? 
The  tottering  step  of  the  aged  invalid  ?  779.  What  is  said  relative  to  the 
structure  of  the  nerves  ?  How  may  they  be  divided  ?  780.  Give  the  nerves 
of  special  sense.  781.  Those  of  general  sensation.  Where  are  the  nerves 
jf  seusution  distributed  :  What  causes  tic  douloureux  ? 


PHYSIOLOGY    OF    THE    NERVOUS    SYSTEM  3f>l 

2d.  The  unpleasant  sensation  sometimes  experienced  when 
we  hear  the  grating  of  a  file  or  saw,  is  produced  by  the  con- 
nection of  the  nerve  that  passes  across  the  drum  of  the  ear 
with  the  fifth  cranial  nerve. 

3d.  When  pressure  is  made  on  the  trunk  of  a  nerve,  the 
sensibility  of  the  part  where  the  nerve  ramifies  is  modified. 
This  is  illustrated,  when  pressure  is  made  upon  the  large 
nerve  of  the  lower  extremity  (sciatic)  in  sitting  upon  a  hard 
bench.  The  foot  is  then  said  to  be  "  asleep." 

4th.  When  the  trunk  of  a  nerve  is  diseased  or  injured,  the 
pain  is  experienced  in  the  outer  extremity  of  the  nerve.  A 
blow  upon  the  elbow,  which  causes  a  peculiar  sensation  in  th« 
little  finger  and  one  side  of  the  ring  finger*  affords  a  familiar 
illustration.  This  sensation  is  produced  by  injuring  the  ulnar 
nerve,  which  is  distributed  to  the  little  finger. 

782.  3d.    Nerves  of  motion.     These  are  the  third,  sixth, 
and  twelfth  pairs  of  cranial   nerves,  and   the   thirty-one  pairs 
of  spinal  nerves.     These  nerves  are  distributed  to  the  fibres 
of  the  five  hundred  muscles  of  the  body.     The  functions  of 
the  muscular  are  different  from  those  of  the  sensitive  nerves. 
The  former  are  provided  for  the  purpose  of  motion,  and  not 
of  feeling.     Hence,  muscles  may  be  cut,  and  the  pain  will  be 
slight,  compared  with  the  cutting  of  the  skin.     This  may  be 
called  muscular  pain.     Weariness  is  a  sensation  recognized 
by  one  set  of  muscular  nerves. 

783.  So  uniformly  is  a  separate  instrument  provided  for 
every  additional  function,  that  there  is  strong  reason  to  regard 
Jie   muscular  nerves,  although  running  in  one  sheath,  as  in 
reality  double,  and  performing  distinct  functions.     Sir  Charles 
Bell,  in  his  work  on  the  Nervous  System,  endeavors  to  show, 

How  is  the  peculiar  sensation  accounted  for  when  we  hear  the  grating 
of  a  file  or  saw  ?  What  produces  the  sensation  when  the  foot  is  said  to 
De  "  asleep  ?  "  "What  is  the  effect  when  the  ulnar  nerve  is  injured  by  a  blow  • 
782.  Give  the  nerves  of  motion.  "What  is  said  of  the  functions  of  the 
muscular  nerves  ?  7^3.  What  does  Sir  Charles  Boll  endeavor  to  show  ? 


#52  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

that  one  set  of  nervous  fibres  conveys  the  mandate  from  the 
brain  to  the  muscle,  and  excites  the  contraction  ;  and  that 
another  set  conveys,  from  the  muscle  to  the  brain,  a  peculiar 
sense  of  the  state  or  degree  of  contraction  of  the  muscle,  by 
which  we  are  enabled  to  judge  of  the  amount  of  stimulus 
necessary  to  accomplish  the  end  desired.  This  is  obviously 
Q.II  indispensable  piece  of  information  to  the  mind  in  regu- 
lating the  movements  of  the  body. 

784.  4th.    Nerves  of  respiration.     These  are  the  fourth, 
seventh,  ninth,  tenth,  and   eleventh    pair  of  cranial  nerves, 
also  the  phrenic  and  the  external  respiratory  nerve.     All  of 
these  nerves  have  their  origin  in  a  distinct  tract  or  column, 
called  the  lateral,  in  the  upper  part  of  the  spinal  cord.    Hence 
it  is  sometimes  named  the  respiratory  column.     These  nerves 
are  distributed  to  one  of  the  muscles  of  the  eye  ;  to  the  mus- 
cles of  the  face  ;  to  the  tongue,  pharynx,  oesophagus,  stomach, 
heart,  lungs,  diaphragm,  and  some  of  the  muscles  of  the  neck 
and  chest. 

785.  It   is   through  the  instrumentality  of  the  accessory, 
phrenic,  and  external  respiratory  nerves,  (10,  11,  12,  13,  fig. 
132,)  that  the  muscles  employed  in  respiration  are  brought 


Fig.  132.  The  distribution  of  the  respiratory  nerves,  a,  Section  of  the  brain  ind 
medulla  oblongata.  ft,  The  lateral  columns  of  the  spinal  cord,  c,  c,  The  respiratory 
tract  of  the  spinal  cord,  d,  The  tongue,  e,  The  larynx.  /,  The  bronchia,  g,  The 
(esophagus.  A,  The  stomach,  i,  The  diaphragm.  1,  The  pneumogaslric  nerve. 
2,  The  superior  laryngeal  nerve.  3,  The  recurrent  laryngeal  nerve.  (These  two 
ramify  on  the  larynx.)  4,  The  pulmonary  plexus  of  the  tenth  nerve.  5,  The  cardiac 
plexus  of  the  tenth  nerve.  These  two  plexuses  supply  the  heart  and  lungs  with  ner- 
vous filaments.  7,  The  origin  of  the  fourth  pair  of  nerves,  that  passes  to  the  superior 
oblique  muscle  of  the  eye.  8,  The  origin  of  the  facial  nerve,  that  is  spread  out  on  the 
«ide  of  the  face  and  nose.  9,  The  origin  of  the  glosso-pharyngeal  nerve,  that  passes 
o  the  tongue  and  pharynx.  10,  The  origin  of  the  spinal  accessory  nerve.  11,  This 
lerve  penetrating  the  sterno-mastoideus  muscle.  12,  The  origin  of  the  internal  res- 
•iratory  or  phrenic  nerve,  that  is  seen  to  ramify  on  the  diaphragm.  13,  The  origin  of 
the  external  respiratory  nerve,  that  ramifies  on  the  pectoral  and  scaleni  muscles. 

784.  Give  the  respiratory  nerves.  What  is  said  in  reference  to  the  respira- 
tory nerves  ?  785.  Through  the  agency  of  what  nerves  are  the  respiratorv 
muscles  brought  into  action  ?  Explain  fig.  132. 


PHYSIOLOGY    OF    THE    NERVOUS    SYSTKM. 

Fig.  132. 


454  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

into  action  without  the  necessity  of  the  interference  of  tho 
mind.  Though  to  a  certain  extent  they  may  be  under  the 
influence  of  the  will,  yet  it  is  only  in  a  secondary  degree.  No 
one  can  long  suspend  the  movements  of  respiration ;  *  for  in 
a  short  time,  instinctive  feeling  issues  its  irresistible  mandate, 
which  neither  requires  the  aid  of  erring  wisdom,  nor  brooks 
the  capricious  interference  of  the  will. 

786.  The  fourth,  seventh,  and  tenth  pairs  of  nerves,  (7,  8, 
9,  fig.  132,)  with  the  spinal  accessory,  phrenic,  and  external 
respiratory,  are  not  only  connected  with  the  function  of  respi- 
ration, but  contribute  to  the  expression  of  the  passions  arid 
emotions  of  the  mind. 

787.  The  influence  of  this  order  of  nerves  in  the  expres- 
sion of  the  passions,  is  strikingly  depicted  in  Sir  Charles  Bell's 
Treatise  on  the  Nervous  System.     "  In  terror,"  he  remarks, 
"  we  can  readily  conceive  why  a  man  stands  with  his  eyes 
intently  fixed  on  the  object  of  his  fears  —  the  eyebrows  ele- 
vated, and    the    eyeballs   largely  uncovered;   or  wh},  wSJi 
hesitating   and   bewildered   steps,  his   eyes  are  rapidly  and 
wildly  in  search  of  something.     In  this  way,  we  only  perceive 
the  intense  application  of  his  mind  to  the  objects  of  his  appre- 
hension, and  its  direct  influence  on  the  outward  organs." 

788.  "  But  when  we  observe  him  further,  there  is  a  spasm 
in  his  breast ;  he  cannot  breathe  freely  ;  the  chest  remains 
elevated,  and  his  respiration  is  short  and  rapid.     There  is  a 


*  Dr.  Elliotson,  and  some  other  writers  on  physiology,  have  detailed 
cases  of  death  from  voluntary  suspension  of  respiration.  But  these 
cases  are  not  conclusive,  as  examinations  were  not  made,  so  as  to 
determine  positively,  that  death  did  not  result  from  disease  of  the 
heart,  brain,  or  some  other  vital  organ. 


Can  respiration  be  suspended  for  any  considerable  length  of  time  r 
786.  What  nerves  contribute  to  the  expression  of  the  passions  and  emo- 
tions of  the  mind  ?  787,  783.  What  does  Sir  Charles  Bell  say  of  the  influ- 
ence of  this  order  of  nerves  in  the  expression  of  the  passions  ? 


PHYSIOLOGY    OF    THE    NERVOUS    SYSTEM.  855 

gasping  and  convulsive  motion  of  his  lips,  a  tremor  on  his 
hollow  cheeks,  a  gasping  and  catching  of  his  throat ;  his 
heart  knocks  at  his  ribs,  while  yet  there  is  no  force  in  the 
circulation  —  the  lips  and  cheeks  being  ashy  pale." 

789.  "  These  nerves   are   the    instruments  of  expression, 
from  the  smile  upon  the  infant's  cheek,  to  the  last  agony  of 
life.     It  is  when  the  strong  man  is  subdued  by  this  mysterious 
influence  of  soul  on  body,  and  when  the  passions  may  be 
truly  said  to  tear  the  heart,  that  we  have  the  most  afflicting 
picture  of  human  frailty,  and    the   most  unequivocal   proof 
'^hat  it  is  the  order  of  functions  we  have  been  considering, 
that  is  thus  affected.     In  the  first  struggle  of  the  infant  to 
draw  breath,  in  the   man   recovering  from  a  state  of  suffoca- 
tion, and  in  the  agony  of  passion,  when  the  breast  labors  from 
the  influence  at  the  heart,  the  same  system  of  parts  is  affected, 
the  same   nerves,  the  same   muscles,  and  the  symptoms  or 
character  have  a  strict  resemblance." 

790.  The   seventh  pair  of  nerves  not  only  communicates 
the  purposes  of  the  will  to  the  muscles  of  the  face,  but  at  the 
same  time  it  calls  them  into  action,  under  the  influence  of 
instinct  and  sympathy.     On  this  subject  a  late  writer  remarks, 
"  How  expressive   is  the  face  of  man  !     How  clearly  it  an- 
nounces the  thoughts  and  sentiments  of  the  mind  !     How  well 
depicted  are  the   passions  on  his  countenance  !    tumultuous 
rage,  abject  fear,  devoted  love,  envy,  hatred,  grief,  and  every 
other  emotion,  in  all  their  shades  and  diversities,  are  imprinted 
there,  in  characters  so  clear  that  he  that  runs  may  read ! 
How    difficult,  nay,  how    impossible,  i«  it  to  hide  or  falsify 
the  expressions  which  indicate  the   internal  feelings  !     Thus 
conscious  guilt  shrinks  from  detection,  innocence  declares  ita 
confidence,  ind  hope  anticipates  with  bright  expectation." 

Observation.     The   fifth  pair  of  nerves   (fig.  126)  is  dis- 

7^9.  Are  they  also  the  instruments  of  expression,  either  of  joy  or  grief? 
790  What  is  said  in  reference  to  the  seventh  pair  of  nerves  ?  Where  is 
'toe  fifth  pair  of  nerves  distributed  ? 


850  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

tributed  to  the  parts  of  the  face  on  which  the  seventh  pair 
ramifies.  The  former  serves  for  sensation,  the  latter  for 
motion.  Thus,  when  the  seventh  pair  of  nerves  is  divided, 
or  its  functions  destroyed  by  disease,  the  side  affected  losea 
all  power  of  expression,  though  sensation  remains  unaffected. 
On  the  contrary,  if  we  divide  the  fifth  pair,  sensation  is 
entirely  destroyed,  while  expression  remains. 

791.  5th.  The  sympathetic  nerve.  This  nerve  confers  vitality 
on  all  the  important  portions  of  the  system.     It  exerts  a  con- 
trolling influence  over  the  involuntary  functions  of  digestion, 
absorption,  secretion,  circulation,  and  nutrition.     Every  por- 
tion of  the  body  is,  to  a  certain  extent,  under  its  influence,  as 
filaments  from  this  system  of  nerves  accompany  the  blood- 
vessels throughout  their  course. 

792.  An  important  use    of  the    sympathetic   nerve   is  to 
form  a  communication  of  one  part  of  the  system  with  another, 
so  that  one  organ  can  take  cognizance  of  the  condition  of 
every  other,  and  act  accordingly.     If,  for  example,  disease 
seizes  the  brain,  the  stomach,  by  its  sympathetic  connection, 
knows  it ;  and  as  nourishment  would  add  to  the  disease,  it 
refuses  to  receive  food,  and   perhaps   throws  off*  what  has 
already  been  taken.     Loss  of  appetite  in  sickness  is  thus  a 
kind  provision  of  nature,  to  prevent  our  taking  food  when  it 
would  be  injurious  ;  and  following  this  intimation,  we,  as  a 
general  rule,  should  abstain  from  food  until  the  appetite  returns. 

Fig.  133.  A  back  view  of  the  brain  and  spinal  cord.  1,  The  cerebrum.  2,  1  be 
cerebellum.  3,  The  spinal  cord.  4,  Nerves  of  the  face.  5,  The  brachial  plexus  of 
nerves.  6, 7, 8, 9,  Nerves  of  the  arm.  10,  Nerves  that  pass  under  the  ribs.  11,  The 
lumbar  plexus  of  nerves.  12,  The  sacral  plexus  of  nerves  13, 14, 15, 16,  Nerves  of 
the  lower  limbs. 

What  is  the  function  of  this  nerve  ?  "What  is  the  effect  if  the  seventh 
pair  is  divided,  or  its  function  destroyed  by  disease  ?  791.  What  is  said  of 
the  sympathetic  nerve  ?  792.  What  is  the  use  of  the  sympathetic  system  t 
Explain  fig.  133. 

Note.  Let  the  anatomy  and  physiology  of  the  nervous  system  be 
reviewed  from  figs.  131, 132,  133,  or  from  anatomical  outline  plate.  No.  8. 


PHYj.DLOGY    OF    THE    NERVOUS    SYSTEM. 

Fig.  133. 


358  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


CHAPTER     XXXIX. 

HYGIENE    OF    THE    NERVOUS    SYSTEM. 

793.  As  the  different  organs  of  the  system  are  dependent 
on  the  brain  and  spinal  cord  for  efficient  functional  action, 
and   as    the    mind    and    brain  are  closely  associated   during 
life,  the  former  acting  in  strict  obedience  to  the  laws  which 
regulate  the  latter,  it  becomes  an  object  of  primary  impor- 
tance   in   education,  to   discover  what   these   laws   are,  that 
we    may   escape   the   numerous   evils   consequent   on   their 
violation. 

794.  For  healthy  and  efficient  action,  the  brain  should  be 
primarily  sound ;  as  this  organ  is  subject  to  the  same  gen- 
eral laws  as  other  parts  of  the   body.     If  the  brain  of  the 
child  is  free  from  defects  at  birth,  and  acquires  no  improper 
impressions  in  infancy,  it  will  not  easily  become  diseased  in 
after  life.     But,  if  the  brain  has  inherited  defects,  or  has  ac- 
quired a  proneness  to  disease  by  mismanagement  in  early  life, 
it  will   more   easily  yield  to  influences  that  cause   diseased 
action.     The  hereditary  tendency  to   disease  is  one  of  the 
most  powerful  causes  that  produce  nervous  and  mental  affec- 
tions.    Consequently,  children  have  a  strong  tendency  to  the 
diseases  from  which  the  parents  suffered. 

795.  When   both  parents   have   similar   defects,  or   have 
descended  from  tainted  families,  the  children  are  usually  more 
deeply  impressed  with  their  imperfections  than  when  only  one 

793 — 850.  Give  the  hygiene  of  the  nervous  system.    793.  Why  is  it  im- 
portant   to    know  the    laws  which    regulate   the   action  of   the  brain  ? 

794.  What  is  necessary  that  the  action  of  the  brain  be  healthy  and  effi 
cient  ?     What  follows  if  the  brain  of  the   child   has    inherited  defects  ? 

795.  What  is  the  effect  when  both  parents  possess  similar  defects  ? 


HYGIENE    OF    THE    NERVOUS    SYSTEM.  353 

possesses  the  defect.  This  is  the  reason  of  the  frequency  of 
nervous  disease  and  imbecility  among  the  opulent,  as  inter- 
marriages among  near  relations  are  more  frequent  with  this 
class  than  among  the  poor. 

Observation.  Among  some  of  the  reigning  families  of 
Europe,  particularly  the  Spanish,  the  folly  of  intermarriage 
among  themselves  is  strongly  illustrated.  The  high  and  noble 
talents  that  characterized  their  progenitors  are  not  seen,  but 
.here  is  now  exhibited,  among  their  descendants,  imbecility 
and  the  most  revolting  forms  of  nervous  disease. 

796.  "  Unhappily,  it  is  not  merely  as  a  cause  of  disease,  that 
hereditary  predisposition  is  to   be    dreaded.     The    obstacles 
which  it  throws  in  the  way  of  permanent  recovery  are  even 
more    formidable,    and    can    never    be    entirely    removed. 
Safety  is    to    be  found    only  in    avoiding    the    perpetuation 
of  the  mischief." 

797.  "  Therefore,  if  two  persons,  each  naturally  of  excitable 
and  delicate  nervous  temperament,  choose  to  unite  for  life, 
they  have  themselves  to  blame  for  the  concentrated  influence 
of  similar  tendencies  in   destroying  the  health  of  their  off- 
spring, and   subjecting  them  to  all  the   miseries  of  nervous 
disease,  madness,  or  melancholy."     The  command  of  God 
not  to  marry  within  certain  degrees  of  consanguinity,  is  in 
accordance   with    the    organic  laws    of  the    brain,   and    the 
wisdom  of  the  prohibition  is  confirmed  by  observation. 

Observation.  The  inhabitants,  females  particularly,  of  the 
sea-girt  islands  of  America,  are  more  affected  with  nervous 
diseases,  than  those  who  reside  upon  the  mainland.  The 
prevalence  of  these  affections  is  ascribed  to  the  frequent 
intermarriage  of  persons  closely  related  by  blood. 


What  is  one  cause  of  nervous  disease  among  the  higher  classes  ?  What 
is  true  of  some  of  the  reigning  families  of  Europe  ?  796.  Why  is  heredi- 
tary predisposition  to  be  dreaded  ?  797-  Is  the  prohilition  of  God  respect- 
ing intermarriage  in  accordance  with  the  organic  laws  of  f  the  brain  ? 
What  is  said  of  the  inhabitants  of  the  sea-girt  islands  of  America  ? 


3SO  ANATOMY     PHYSIOLOGY,    AND    HYGIENE. 

798.  The  brain  requires  a  due  supply  of  pure  blood.    This 
organ  receives  an  unusually  large  supply  of  blood,  in  com- 
parison with  the  rest  of  the  body.     It  is  estimated  that  one 
tenth  of  all  the  blood  sent  from  the  heart  goes  to  this  organ. 
If  the  arterial  blood   be  altogether  withdrawn,  or  a  person 
breathes  air  that  is  filled  with  carbonic  gas,  the  brain  ceases 
its  proper  action,  and  sensibility  with  consciousness  becomes 
extinct. 

Illustrations.  1st.  If  a  person  lose  a  considerable  quantity 
of  blood,  dizziness  and  loss  of  consciousness  follow.  This 
results  from  the  brain  not  receiving  a  sufficient  amount  of 
blood  to  sustain  its  functions. 

2d.  When  an  individual  descends  into  a  well  or  pit  that  con- 
tains carbonic  acid,  the  blood  is  not  changed  or  purified  in 
the  lungs,  and  loss  of  consciousness  and  death  soon  follow. 

799.  The  slighter  variations  in  the  state  of  the  blood  have 
equally  sure,  though  less  palpable  effects.     If  its  vitality  is 
impaired  by  breathing  an  atmosphere  so  much  vitiated  as  to 
be  insufficient  to  produce  the  proper  degree  of  oxygenation, 
the  blood  then  affords  an  imperfect  stimulus  to  the  brain.     As 
a  necessary  consequence,  languor  and  inactivity  of  the  men- 
tal and  nervous  functions  ensue,  and  a  tendency  to  headache, 
fainting,  or  hysteria,  makes  its  appearance. 

Observations.  1st.  Let  a  person  remain,  for  a  time,  in  a 
crowded,  ill-ventilated,  hall  or  church,  and  headache  or  fairit- 
ncss  is  generally  produced.  This  is  caused  by  the  action  of 
impure  blood  upon  the  brain. 

2d.  If  a  school-teacher  wishes  to  have  his  pupils,  on  the 
J«ay  of  examination,  appear  creditably,  he  will  be  careful  to 
lave  the  room  well  ventilated.  Ventilating  churches  might 

798.  Why  does  the  brain  require  a  due  supply  of  pure  blood  ?  What  is  the 
effect  when  a  person  loses  a  considerable  quantity  of  blood  ?  What  causes 
the  loss  of  consciousness  when  carbonic  acid  is  breathed  ?  799.  What 
effects  are  produced  by  slight  variations  in  the  quality  of  the  blood  ?  From 
the  following  observations,  give  some  of  the  effects  of  impure  blood  ou 
the  brain. 


HYGIENE    OF    THE    NERVOUS    SYSTEM.  31 

prevent    the   inattention    and    sleepiness    that   are    observed 
during  the  afternoon  service. 

3d.  In  many  instances,  the  transmission  of  imperfectly 
oxygenated  blood  to  the  brain,  is  an  influential  cause  in  the 
production  of  nervous  disease  and  delicacy  of  constitution. 
The  only  efficient  remedy  for  these  conditions  is  a  supply  of 
pure  blood  to  the  brain. 

800.  The  brain  should  be  called  into  action.     This  organ, 
like  the  muscles,  should  be  used,  and  then  allowed  to  rest,  or 
cease  from  vigorous   thought.     When  the  brain  is  properly 
called  into  action  by  moderate  study,  it  increases  in  size  and 
strength  ;  while,  on  the   other  hand,  if  it  is   not  used,  the 
action  of  this  organ    is   enfeebled,  thereby  diminishing   the 
function  of  all  parts  of  the  body. 

801.  The  brain,  being  an  organized  part,  is  subject,  so  far 
as  regards  exercise,  to  the  same  laws  as  the  other  organs  of 
the  body.     If  it  is  doomed  to  inactivity,  its  size  diminishes,  its 
health  decays,  and   the   mental  operations  and  feelings,  as  a 
necessary  consequence,  become  dull,  feeble,  and  slow.     If  it 
is  duly  exercised  after  regular  intervals  of  repose,  the  mind 
acquires  readiness  and  strength.     Lastly,  if  it  is  overtasked, 
cither  in  the  force  or  duration  of  its  activity,  its  functions 
become  impaired,  and  irritability  and  disease  take  the  place  of 
health  and  vigor. 

802.  The  consequences  of  inadequate  exercise  will  first  be 
explained.     We  have  seen  that  by  disuse  the  muscles  become 
emaciated,  the  bones  soften,  and  the  blood-vessels  are  oblit- 
erated.    The  brain  is  no  exception  to  this  general  rule.     It  is 
impaired    by    permanent  inactivity,  and   becomes  less  fit  to 
manifest  the  mental  powers  with  readiness  and  energy.     Nor 
will  this  surprise  any  reflecting  person,  who  considers  that  the 

800.  Why  should  the  brain  be  called  into  action  ?  801.  What  is  the 
effect  if  the  brain  is  doomed  to  inactivity  ?  802.  Show  the  consequences  ot 
disuse  of  the  organs  mentioned  in  preceding  chapters.  Does?  the  same 
principle  apply  to  tin-  brain  : 


t-Joy  ANATOMY,    PHYSFOLOGY,    AND    HYGIENE. 

brain,  as  a  part  of  the  same  animal  system,  is  nourished  by 
the  same  blood  and  regulated  by  the  same  vital  laws  as  the 
muscles,  bones,  and  arteries. 

803.  It  is  the  weakening  and  depressing  effect  which   is 
induced  by  the    absence   of  the  stimulus  necessary   for  the 
healthy  exercise  of  the  brain,  that  renders  solitary  confine- 
ment so  severe  a  punishment,  even  to  the  most  daring  minds. 
Keeping  the  above  principle  in  view,  we  shall  not  be  surprised 
to  find  that  non-exercise  of  the  brain  and  nervous  system,  or, 
in  other  words,  inactivity  of  intellect  and  feeling,  is  a  verv 
frequent  predisposing  cause  of  every  form  of  nervous  disease. 

804.  For  demonstrative  evidence  of  this  position,  we  have 
only  to  look  at  the  numerous  victims   to   be  found  among 
females  of  the  middle  and  higher  ranks,  who  have  no  calls  tf 
exertion  in  gaining  the  means  of  subsistence,  and  no  object? 
of  interest  on  which  to  exercise  their  mental  faculties,  an« 
who,   consequently,  sink    into   a   state    of  mental  sloth  am 
nervousness,  which  not  only  deprives  them  of  much  enjoy 
ment,  but  subjects  them  to  suffering,  both  of  body  and  mind 
from  the  slightest  causes. 

805.  But  let  the   situation   of  such   persons  be  changed ; 
bring  them,  for  instance,  from  the  listlessness  of  retirement 
to  the  business  and  bustle  of  the  city ;  give  them  a  variety  of 
imperative  employments,  and  so  place  them  in  society  as  ti? 
supply  to  their  cerebral  organs  that  extent  of  exercise  which 
gives  health  and  vivacity  of  action,  and  in  a  few  months  the 
change  produced  will  be  surprising.     Health,  animation,  and 
energy,  will  take  the  place  of  former  insipidity  and  dulness. 

806.  An  additional  illustration,  involving  an  important  prii. 
ciple  in  the  production  of  many  distressing  forms  of  disease 


803.  What  renders  solitary  confinement  so  severe  a  punishment  to  the 
most  daring  minds  ?  What  is  a  predisposing  cause  of  nervous  disease  ? 
804.  In  what  classes  do  mental  and  nervous  debility  prevail  ?  805.  How 
can  this  be  counteracted  ?  806.  Give  another  illustration,  showing  how 
disease  of  the  brain  is  induced. 


HYGIENE    OF    THE    NEKVOUS    SYSTEM.  SG'.l 

will  be  found  in  the  case  of  a  man  of  mature  age,  and  of 
active  habits,  who  has  devoted  his  life  to  the  toils  of  business, 
and  whose  hours  of  leisure  have  been  few  and  short.  Sup- 
pose such  a  person  to  retire  to  the  country  in  search  of  repose, 
and  to  have  no  moral,  religious,  or  philosophical  pursuits  to 
occupy  his  attention  and  keep  up  the  active  exercise  of  his 
brain ;  this  organ  will  lose  its  health,  and  the  inevitable  result 
will  be,  weariness  of  life,  despondency,  or  some  other  variety 
of  nervous  disease. 

807.  One  great  evil  attending  the  absence  of  some  imper- 
ative employment  or  object  of  interest,  to  exercise  the  mind 
and  brain,  is  the  tendency  which  it  generates  to  waste  the 
mental  energies  on  every  trifling  occurrence  which  presents 
itself,  and  to  seek  relief  in  the  momentary  excitement  of  any 
sensation,  however   unworthy.     The    best  remedy  for  these 
evils  is  to  create  occupation  to  interest  the  mind,  and  give 
that  wholesome  exercise  to  the  brain,  which  its  constitution 
requires. 

808.  The  evils  arising  from  excessive  or  ill-timed  exercise 
oj  the  brain,  or  any  of  its  parts,  are  numerous.     When  we 
use  the  eye  too  long,  or  in  too  bright  a  light,  it  becomes  blood- 
shot.    The  increased  action  of  its  vessels  and  nerves  gives 
rise  to  a  sensation  of  fatigue  and  pain,  requiring  us  to  desist. 
If  we  relieve  the  eye,  the  irritation  gradually  subsides  and 
the  healthy  state  returns.     But,  if  we  continue  to  look  intently, 
or  resume  our  employment  before  the  eye  has  regained  its 
natural  state  by  repose,  the  irritation  at  last  becomes  perma- 
nent, and  disease,  followed  by  weakness  of  vision,  or  even 
blindness,  may  ensue. 

809.  Phenomena  precisely  analogous  occur,  when,  from 

807.  What  is  one  great  evil  attending  the  absence  of  some  imperative 
employment  to  exercise  the  mind  and  brain  ?  What  is  the  true  remedy  for 
these  evils  ?  808.  From  what  other  cause  do  evils  arise  to  the  brain  ? 
Explain  the  evil  of  it  by  the  excessive  use  of  the  eye.  809.  What  is  the 
jnly  difference  in  the  analogy  of  the  phenomena  of  the  eye  and  brain  ?  Has 
the  aualugy  becu  verified  ? 


364  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

intense  mental  excitement,  the  brain  is  kept  long  in  a  state  of 
excessive  activity.  The  only  difference  is,  that  we  can  always 
see  what  happens  in  the  eye,  but  rarely  what  takes  place  in 
the  brain  ;  occasionally,  however,  cases  of  fracture  of  the  skull 
occur,  in  which,  part  of  the  bone  being  removed,  we  can  see 
(he  quickened  circulation  in  the  vessels  of  the  brain,  as  easily 
as  those  of  the  eye. 

810.  Sir  Astley  Cooper  had  a  young  man  brought  to  him, 
who  had  lost  a  portion  of  his  skull,  just  above  the  eyebrow. 
"  On  examining  the  head,"  says  Sir  Astley,  "  I  distinctly  saw 
that  the  pulsation  of  the  brain  was  regular  and  slow ;  but  at 
this  time  he  was  agitated  by  some  opposition  to  his  wishes, 
and  directly  the  blood  was  sent  with  increased   force  to  the 
brain,  and  the  pulsation  became  frequent  and  violent." 

811.  Indeed,  in  many  instances,  the   increased  circulation 
in  the  brain,  attendant  on  mental  excitement,  reveals  itself 
when  least  expected,  and  leaves  traces  after  death,  which  are 
?erv  nerceptible.     When  tasked  beyond  its  strength,  the  eye 
becomes  insensible  to  light,  and  no  longer  conveys  any  im- 
pressions to  the  mind.     In  like  manner,  the  brain,  when  much 
exhausted,  becomes  incapable  of  thought,  and  consciousness 
is  almost  lost  in  a  feeling  of  utter  confusion. 

812.  At  any  time  of  life,  excessive  and  continued  mental 
exertion  is  hurtful ;  but  in  infancy  and  ear'y  youth,  when  the 
structure  of  the  brain  is  still  immature  and  delicate,  perma- 
nent mischief  is  more  easily  produced  by  injudicious  treat- 
ment than  at  any  subsequent    period.     In   this  respect,  the 
analogy  is  as  complete  between  the  brain  and  the  other  parts 
of  the  body,  as  that  exemplified  in  the  injurious  effects  of  pre- 
mature exercise  of  the  bones  and  muscles. 

813.  Scrofulous  and  rickety  children  are  the  most  usual 

810.  Relate  the  case  detailed  by  Sir  Astley  Cooper.  811.  May  the 
increased  functional  action  of  the  brain  change  its  structure  ?  812.  At 
what  age  particularly  is  excessive  and  continued  mental  exertion  hurtful  ' 
313  What  is  said  of  scrofulous  and  rickety  children  ? 


HYGIENE    OF    THE    NERVOUS    SYSTEM.  3Gil 

sufferers  in  this  way.  They  are  generally  remarkable  for 
large  heads,  great  precocity  of  understanding,  and  small,  deh- 
cate  bodies.  But  in  such  instances,  the  great  size  of  the  brain, 
and  the  acuteness  of  the  mind,  are  the  results  of  morbid 
growth.  Even  with  the  best  of  management,  the  child  passes 
the  first  years  of  its  life  constantly  on  the  brink  of  active 
disease. 

814.  Instead,  however,  of  trying   to   repress   its   mental 
activity,  the   fond  parents,  misled   by  the  early  promise  of 
genius,,  too  often  excite  it  still  further,  by  unceasing  cultiva- 
tion, and    the  never-failing   stimulus  of  praise.     Finding  its 
progress  for  a  time  equal  to  their  warmest  wishes,  they  look 
forward  with  ecstasy  to  the  day  when  its  talents  will  break 
forth  and  shed  lustre  on  its  name. 

815.  But   in   exact    proportion    as   the    picture   becomes 
brighter  to  their  fancy,  the  probability  of  its  being  realized 
becomes  less;  for  the  brain,  worn  out  by  premature  exertion, 
either  becomes  diseased,  or  loses  its  tone,  leaving  the  mental 
powers  imbecile  and  depressed  for  the  remainder  of  life.    The 
expected  prodigy  is  thus  easily  outstripped  in  the  social  race 
by  many  whose  dull  outset  promised  him  an  easy  victory. 

816.  Taking  for  our  guide  the  necessities  of  the  constitu- 
tion, it  will  be  obvious  that  the  modes  of  treatment  commonly 
resorted  to  ought  to  be  reversed.     Instead  of  straining  to  the 
utmost  the  already  irritable  powers  of  the  precocious  child, 
and  leaving  his  dull  competitor  to  ripen  at  leisure,  a  systematic 
attempt  ought  to  be  made,  from  early  infancy,  to  rouse  to  action 
the  languid  faculties  of  the  latter,  while  no  pains  ought  to  be 
spared  to  moderate  and  give  tone  to  the  activity  of  the  former. 

817.  Instead  of  this,  however,  the  prematurely  intelligent 
child  is  sent  to  school  and  tasked  with  lessons  at  an  unusuallv 

814.  How  aie  such  children  usually  managed  ?  815.  What  is  the  cause 
of  their  early  promise  and  subsequent  disappointment  ?  816.  What  mode 
of  treatment  should  be  adopted  in  educating  precocious  children  ? 
817.  How  should  the  dull  or  less  active  child  be  treated?  What  is  the 
UGaul  course? 


3lit>  ANATOMY,    PHYSIOLOGY,    AND    HYliIENE. 

early  age,  while  the  healthy  but  more  backward  boy,  whc 
requires  to  be  stimulated,  is  kept  at  home  in  idleness,  per- 
haps for  two  or  three  years  longer,  merely  on  account  of 
fiis  backwardness.  A  double  error  is  here  committed.  The 
consequences  to  the  intelligent  boy  are,  frequently,  the  per- 
manent loss  both  of  health  and  of  his  envied  superiority  of 
intellect. 

818.  In  youth,  too,  much    mischief  is  done  by  the   long 
daily  period  of  attendance  at  school,  and  the  continued  appli- 
cation of  the  mind  which  the  ordinary  system  of  education 
requires.     The  law  of  exercise  —  that  long-sustained  action 
exhausts  the  vital  powers  of  the  organ  —  applies  as  well  to 
the  brain  as  to  the  muscles.     Hence  the  necessity  of  varying 
the  occupations  of  the  young,  and  allowing  frequent  intervals 
of  exercise  in  the  open  air,  instead  of  "  enforcing  the  continued 
confinement  now  so  common." 

Observation.  It  is  no  unusual  occurrence,  that  on  examina- 
tion day,  the  best  scholars  appear  indifferently.  This  may  be 
the  result  of  nervous  exhaustion,  produced  by  extra  mental 
effort  in  preparing  for  the  final  examination.  It  is  advisable 
for  such  pupils  to  divert  their  minds  from  close  study  for  a 
few  days  previous  to  examination.  During  this  time,  the 
student  may  indulge  in  physical  recreation,  social  intercourse, 
and  a  moderate  amount  of  reading. 

819.  "  In  early  and  middle   life,  fever,  an  unusual  degree 
of  cerebral  disorder,  is  a  common  consequence  of  the  exces- 
sive and  continued  excitement  of  the  brain.     This  unhappy 
result  is  brought  on  by  severe  study,  unremitted  mental  exer- 
tion, anxiety,  and  watching.     Nervous  disease,  from  excessive 
mental  labor  and  high  mental  excitement,  sometimes  shows 
itself  in  another  form. 


What  are  the  consequences  of  the  error  ?  818.  What  error  prevails  in  the 
present  system  of  education  ?  Why  should  youths  be  allowed  frequent 
intervals  to  exercise  in  the  open  air  ?  Give  observation.  819.  What  is  a 
frequent  consequence  of  continued  and  excessive  excitement  of  the  brain  ? 


HYGIENE    OF    THE    NERVOUS    SYSTEM.  t*t7 

820.  "  From  the  want  of  proper  intervals  of  rest,  the  vascu- 
ar  excitement  of  the  brain  has  not  time  to  subside.  A  restless 
irritability  of  temper  and  disposition  comes  on,  attended  with 
sleeplessness  and  anxiety,  for  which  no  external  cause  can  be 
assigned.  The  symptoms  gradually  become  aggravated,  the 
digestive  functions  give  way,  nutrition  is  impaired,  and  a 
sense  of  wretchedness  is  constantly  present,  which  often  leavls 
to  attempts  at  suicide." 

Observations.  1st.  Moderation  in  mental  exertion  is  more 
necessary  in  old  age  than  in  early  or  mature  years.  In  youth 
and  manhood,  the  exhaustion  of  the  brain  from  over-excite- 
ment may  be  repaired,  but  no  such  result  follows  over-exer- 
tion in  the  decline  of  life.  "  What  is  lost  then,  is  lost  forever." 
At  that  period,  the  brain  becomes  excited,  and  is  soon  exhausted 
when  forced  to  protracted  and  vigorous  thought.  Sir  Walter 
Scott  and  President  Harrison  afford  sad  examples  of  prema- 
ture  death  from  overtasked  brains  at  an  advanced  period  of 
Uieir  lives. 

2d.  If  the  mind  is  incessantly  engaged  in  the  contemplation 
of  the  same  object,  there  is  danger  from  over-exertion  of  the 
brain  at  any  period  of  life,  but  more  particularly  in  old  age. 
The  more  limited  the  sphere  of  mental  action,  the  greater  the 
danger  of  the  brain  being  over-exercised.  Hence  the  fre- 
quency of  nervous  diseases  in  poets,  mathematicians,  and 
musicians. 

820.  What  often  manifests  itself  from  the  want  of  proper  intervals  of 
rest  ?  Why  is  moderation  in  mental  action  necessary  in  old  age  ?  What 
is  the  effect  if  the  mind  is  incessantly  engaged  in  the  contei  iplation  of  the 
game  object  ? 


ANATOMY,    PIIV:nuI..U'.;y,    A\.0    HVG1KNE. 


CHAPTER     XL. 

HYGIENE  OF  THE  NERVOUS  SYSTEM,  CONTINUED. 

821.  HAVING  pointed  out  the  evils  arising  both  from  inade- 
quate and  from  excessive  mental  exertion,  it  remains  to  direct 
the  attention  to  some  of  the  rules  which  should  guide  us  in 
the  exercise  of  the  brain. 

822.  We  should  not  enter  upon  continued  mental  exert.ion, 
or  arouse  deep  feeling,  immediately  before   or  after  a  full 
meal.     Such  is  the  connection  between  the  mind  and  body, 
that  even  in  a  perfectly  healthy   person,   unwelcome   news, 
sudden  anxiety,  or  mental  excitement,  occurring  soon  after 
eating,  will  impede  digestion,  and  cause  the  stomach  to  loathe 
the  masticated  food. 

823.  The  worst  forms  of  indigestion  and  nervous  depres- 
sion are  those  which  arise  from  excessive  mental  application, 
or  depressed  feeling,  conjoined  with  unrestrained  indulgence  in 
the  pleasures  of  the  table.     In  such  circumstances,  the  stom- 
ach and  brain  react  upon  and  disturb  each  other,  till  all  the 
horrors  of  nervous  disease  make  their  unwelcome  appearance, 
and    render   life    miserable.      Too    many  literary  men   and 
students  know  this  from  sad  experience. 

824.  We  should  engage  in  intense  study  in  the  early  part 
oj  the  day.     Nature  has  allotted  the  darkness  of  the  night  for 
repose,  and  for  restoration  by  sleep  of  the  exhausted  energies 
of  mind  and  body.    In  the  early  part  of  the  evening,  if  study 
or  composition  be  ardently  engaged  in,  the  increased  action 


822.  Why  should  Ave  not  arouse  deep  feeling  immediately  before  or  aftei 
rating  a  full  meal  ?  823.  How  are  the  worst  forms  of  indigestion  and  ner- 
\'i;ns  depression  produced  ?  What  class  of  men  know  this  from  sad  experi 
?nce  ?  824.  What  evils  arise  from  studious  application  at  night  ? 


HYGIENE    OF    THE    NERVOUS    SYSTEM.  'j(>9 

of  the  brain,  which  always  accompanies  activity  of  mind, 
requires  a  long  time  to  subside.  If  the  individual  possesse*  a 
nervous  temperament,  he  will  be  sleepless  for  hours  after  he 
has  retired,  or  perhaps  be  tormented  by  unpleasant  dreams. 

825.  It  is,  therefore,  of  great  advantage  to  enter  upon 
intense    mental  application  early  in  the  day,  and  to  devote 
several  of  the  hours  which   precede  bedtime  to  entertaining 
conversation,  music,  and  lighter  reading.    The  vascular  excite- 
ment ]  reviously  induced  in  the  brain  by  study,  has  then  time 
to  subside,  and  sound,  refreshing   sleep  is  much  more  cer- 
tainly obtained.     This  rule  is  of  great  consequence  to  those 
who  are  obliged  to  undergo  much  mental  labor. 

Observation.  The  idea  of  gathering  wisdom  by  burning 
the  "  midnight  oil,"  is  more  poetical  than  profitable.  The 
best  time  to  use  the  brain  is  during  the  day. 

826.  The  close  student  and  the  growing  child  need  more  sleep 
than  the  idler  or  the  adult.     As  sleep  is  the  natural  repose  of 
all  organs,  it  follows  that  the  more  the  brain  and  other  organs 
of  the  system  are  employed,  the  more  repose  they  require 
The  organs  of  the  child,  beside  sustaining  their  proper  func- 
tions, are  busy  in  promoting  its  growth.     This  nutritive  process 
is  attended  with  a  certain  degree  of  exhaustion.     The  impaired 
health  of  children  often  results  from  a  disregard  of  this  prin- 
ciple.    But,  on  the  other  hand,  an  excess  of  sleep  produces 
feebleness,  by  preventing  the  proper  exercise  of  the  mind  a^ 
well  as  the  body. 

827.  The  length  of  time  the  brain  may  le  advantageously 
used,  is  modified  by  many  circumstances.     The  power  of  the 
brain  in  different  persons  to  endure  action,  is  various.     This 
is   modified  by  its  primary  character  ;    by  development  and 
age ;  by  habits  of  action  ;  by  the  health  of  the  cerebral  organ 

825.  Why  should  we  engage  in  intense  study  in  the  early  part  of  the  duy  ? 
826.  What  persons  require  the  most  sleep?  Why?  827.  What  is  said 
relative  to  the  length  of  time  that  the  brain  can  he  advantageously  used  ? 
CJivt  u.  condition  that  modifies  the  amount  of  mental  labor. 


370  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

and  general  system;  by  the  moral  feelings  and  other  con- 
ditions. 

828.  The    primary  physical  organization   of  some   indi« 
viduals  is  such,  that  they  are  enabled  to  endure  with  impunity 
an  amount  of  mental  labor  that  would   disorder,  if  not  de- 
stroy functionally,  the   cerebral   organ   of  others    differently 
constituted.    Napoleon  Bonaparte  was  of  this  number.    There 
can  be  no  fixed  period  for  mental  labor,  that  may  be  adopted 
as  a  rule  for  all  persons  whose  systems  are  maturely  developed. 
Much  less  is  there  a  proper  definite  period  for  study,  that  is 
applicable  to  all  children. 

Observation.  The  practice  of  retaining  pupils  of  all  ages, 
from  five  to  twenty  years,  in  the  school-room  the  same  period  of 
time,  for  the  purpose  of  study,  is  not  predicated  upon  any  law 
of  physiology.  An  exercise  of  three  hours,  with  one  or  two 
recesses  of  ten  minutes  each,  may  profit  the  eldest  class  ;  two 
hours  with  a  recess  of  ten  minutes,  the  middle  class;  while 
one  hour,  or  one  hour  and  a  half,  with  one  recess,  would  be  as 
long  a  period  as  the  youngest  pupils  should  be  retained  in  the 
study-room  at  one  session. 

829.  A  person   who  is  accustomed  to    muscular  exertion 
will  endure  a  longer  period  of  physical  toil  than  one  who  is 
not  inured  to  it.     So  it  is  with  mental  labor.     If  the  brain  has 
been  habituated  to  mental  action  and  profound  study,  it  will 
not   be  so   soon  fatigued   as  when   not  accustomed  to  such 
exertions ;  consequently,  an  amount  of  mental  labor  may  be 
performed  with  impunity  at  one  time,  that  would  exhaust  and 
cause  serious  disease  of  the  cerebral  organ  at  another. 

Observation.  Persons  that  commence  a  course  of  study 
at  a  late  period  in  life,  frequently  evince  their  zeal  at  the 

828.  "Why  can  there  be  no  fixed  period  for  mental  labor  ?  "What  is  said 
of  the  practice  of  retaining  pupils  of  all  ages  the  same  period  of  time  in 
the  school-room  ?  829.  Show  that  the  action  of  the  brain  is  influenced  h\ 
habit,  as  well  as  the  muscular  system.  What  suggestion  to  those  persons 
that  commence  a  course  of  study  at  a  late  period  in  life  ? 


HYGIENE    OF    THE    NERVOUS    SYSTEM.  Ifi  1 

commencement  by  poring  over  their  books  twelve  or  more 
hours  each  day.  The  progress  of  such  students  is  soon 
arrested  by  physical  and  mental  depression.  In  sucli  instances, 
it  would  be  more  judicious  to  commence  with  only  three  or 
four  hours'  vigorous  application  each  day,  and  gradually  pro- 
tract the  period  of  study  five  or  more  minutes  every  succes- 
sive day,  until  the  brain  may  be  called  into  vigorous  action  six 
or  eight  hours  with  impunity. 

830.  The   amount  of  mental  power  is  greatly  influenced 
by  the  general  health.     Such  is  the  intimate  connection  of  the? 
different  parts  of  the  system,  particularly  the  digestive  appaia 
tus,  with  the  cerebral  organs,  that  except  there  be  vigor  oi 
constitution,  and  freedom  from  disease,  mental  efforts  will  be 
feeble  and  of  little  avail. 

Observation.  The  prevalent  opinion,  that  individuals  who 
are  feeble  or  diseased  may  acquire  a  collegiate  education,  and 
thus  become  useful  to  themselves  and  the  community,  is  very 
generally  erroneous.  Such  persons  should  enter  upon  a  daily 
and  systematic  course  of  physical  training,  and  their  labor 
should  be  in  the  open  air,  in  order  that  the  system  may  be 
invigorated  and  freed  from  disease. 

831.  The  moral  feelings,  exert  a  controlling  influence  over 
the    functions    of  the    muscular,    digestive,   and   respiratory 
organs.     They  also  exert  an  influence,  perhaps,  more  pow- 
erful  upon  the    nervous    system.      While  fear  and   anxiety 
depress,  hope  and  the  enlivening  emotions,  facilitate  the  func- 
tional activity  of  the  brain,  and  increase  its  power  for  mental 
exertion.      By  a  proper   and    systematic   education    of    the 
moral  feelings,  they  are  not  only  a  source  of  happiness,  and 
productive   of  right  conduct,  but   aid    in  the  culture  of  the 

830.  Show  that  the  amount  of  mental  power  is  modified  by  the  general 
Health.  What  is  said  of  feeble  persons  acquiring  a  collegiate  education  '{ 
SJ1.  Do  the  moral  feelings  exert  a  controlling  influence  over  the  principal 
functions  of  the  system  ?  What  is  the  effect  of  a  proper  and  systematic 
culture  of  the  moral  feelings  ? 


'A~i'<i  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

intellect.  Consequently,  we  should  cultivate  a  feeling  of  hope- 
ful trust  in  the  future,  and  a  firm  reliance  upon  the  laws  which 
the  Creator  has  given  us  for  our  guidance. 

832.  Regularity  is  very  important  in  exercising  the  moral 
and  intellectual  powers.     Periodicity,  or  a  tendency  to  resume 
the  same  mode  of  action  at  stated  times,   is  peculiarly  the 
characteristic  of  the  norvous  system.     If  we  repeat  any  kind 
of  mental  effort  every  day  at  the  same  hour,  we  at  last  find 
ourselves  entering  upon   it  without   premeditation  when  the 
time  approaches.     In  like  manner,  if  we  arrange  our  studies 
in  accordance  with  this  law,  and  take  up  each  in  the  same 
order,  a  natural  aptitude   is  soon  produced,   which  renders 
application  more  easy  than  by  resuming  the  subjects  as  acci- 
dent may  direct. 

Observation.  When  engaged  in  abstruse  studies,  it  may  be 
found  advantageous  to  pursue  others  that  are  less  difficult. 
The  intense  application  of  the  brain,  which  is  requisite  in  the 
one  instance,  is  relieved  by  directing  the  attention  to  a  study 
that  requires  less  thought.  By  this  change,  there  is  mental 
relaxation  attended  with  invigoration  of  the  cerebral  organ. 
Or,  it  may  be  explained  by  assuming,  that  the  brain  is  com- 
posed of  an  aggregate  of  distinct  organs,  each  of  which  is 
called  into  action  in  pursuing  different  studies. 

833.  Effective    study  is  impossible  if  the    powers  of  the 
brain  are   depressed.     When  the  cerebral    organ   has   been 
temporarily  debilitated  by  protracted  intellectual  efforts,  it  is 
ineffectual  to  attempt  any  concentrated  mental  exercise.     This 
condition  of  the  nervous  system  is  indicated  by  confusion  of 
thought  and  inability  to  attain  results  that  usually  follow  simi- 
lar efforts.     Mental  rest  in  these  cases  is  required, 

Observation.      Students  frequently  fail   in  solvir.g  mathe- 

832.  Why  is  regularity  of  great  importance  in  exercising  the  moral  and 
intellectual  powers  ?  What  suggestion  when  pursuing  abstruse  studios  : 
How  explained  ?  833.  When  is  effective  study  impossible  ?  How  is  this 
condition  of  *.he  nervous  system  indicated  ? 


HYGIENE    OF   THE    NERVOUS    SYSTEM  373 

matical  problems  when  the  mind  is  prostrated  by  continued 
and  excessive  effort  to  obtain  a  solution.  Not  imfrequenily 
after  a  night's  rest  the  problem  is  quickly  solved,  and  the 
pupil  thinks  he  "  dreamed  it  out."  The  true  explanation  is 
rest  invigorated  the  exhausted  brain,  which  fitted  it  for  vigor- 
ous and  successful  thought. 

834.  The  intellect  should  not  be  cultivated  to  the  neglect 
of  the  moral  and  physical  powers.     All  the  faculties  require 
for  their  development  regular  exercise,  alternated  with  inter- 
vals of  rest.     This  is  as  necessary  to  the  due  development 
of  the  moral  feelings  of  a  child  as  in  physical  training  and 
mental  culture.     Consequently,  those  schools  are  to  be  pre- 
ferred in  the  education  of  youth,  where  the  physical,  inte  lee- 
tual,  and  moral  faculties  receive   each  day  a  due  share  of 
attention  and  culture. 

835.  The  continuance  of   healthy  and  vigorous  action  in 
the  matured   physical,    mental,  and  moral    powers,  requires 
frequent  and  regular  action,  alternated  with  rest,  as  much  as 
in  their  development.     Consequently,  those  who  cultivate  one 
or  two  of  these  faculties,  to  the  neglect  of  the  others,  exhibit 
a    marked  deficiency  of   acuteness   and   vigor  in  those  not 
exercised.     This  defect  reacts  on  the  powers  that  are  vigor- 
ous, diminishing  the  energy  and  deteriorating  all  the  other 
faculties  of  man. 

Observations.  1st.  If  the  principles  before  mentioned  are 
true,  the  adult,  as  well  as  the  child,  should  spend  a  part  of 
each  day  in  some  proper  physical  employment ;  another  por 
tion  should  be  appropriated  to  intellectual  pursuits ;  while 
another  should  be  sedulously  devoted  to  the  cultivation  of 
the  moral  feelings. 

2d.    Disease  of  the  corporeal  system  more  frequently  occu  rs 

How  is  the  "  dreaming  out"  of  problems  explained  ?  834.  What  is  said 
of  the  culture  of  the  intellect  ?  What  schools  are  preferable  in  the  edu- 
cation of  youth  ?  Why  ?  835.  What  is  the  effect  of  cultivating  only  t.n< 
faculty  of  the  mind  ?  Give  observation  1st.  Observation  2d. 


374  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

when  only  one  set  of  faculties  is  used  than  when  all  are 
equally  employed.  This  is  particularly  true  of  nervous  and 
mental  disease,  which  follows  and  is  caused  by  either  high 
intellectual  action,  or  intense  moral  emotions,  without  a  due 
amount  of  physical  exercise. 

836.  The  brain  can  exercise  its  full  force  upon  only  one 
object  at  a  time.     If  its  energies  are  directed  to  two  or  more 
operations,  neither  will  receive  that  full  power  of  exertion  that 
it  would  if  only  one  object  had  engaged  the  mind.     Although 
the  brain  will  direct  several  operations  at  the  same  time  when 
only  slight  mental  effort  is  required,  yet  when  one  operation 
becomes  difficult,  or  demands  special  attention  of  the  mind, 
the  other  will   be   suspended.      This  is  illustrated    in  social 
conversation  while  walking.     Let  it  become  necessary  to  con- 
centrate the  nervous  power  upon  the  motor  organs,  and  the 
conversation  declines  or  ceases. 

837.  In  acquiring  an  education,  or  in  pursuing  any  profes- 
sion or  trade,  none  of  those  influences  that  promote  the  propel 
functions  of  the    body,  and  tend  to  increase  physical  ease, 
should  be  neglected.     For,  if  the  brain  is  occupied  with  dis- 
agreeable  sensations,  it  cannot  concentrate  its  power  as  effec- 
tively in  the  various  employments  of  man. 

Observations.  1st.  The  situation,  ventilation,  light,  and 
warmth  of  a  school-room,  together  with  the  arrangement  of 
the  benches,  do  much  to  influence  the  concentration  or  dis- 
traction of  the  operations  of  the  mind.  Let  there  be  attached 
to  the  school -house  a  spacious  yard  planted  with  trees ;  let  its 
architecture  be  attractive ;  let  the  windows  be  arranged  with 
regularity,  and  not  with  the  elevation  of  a  convict's  cell,  and 
the  benches,  in  every  respect,  be  adapted  to  the  different 
scholars,  so  that  the  position  of  each  may  be  comfortable,  and 

836.  What  is  the  effect  if  the  brain  concentrates  its  energies  on  more 
than  one  object  at  a  time?  How  illustrated?  837.  "What  should  be  re- 
garded in  pursuing  any  employment  ?  Why  ?  What  is  said  in  reference 
to  the  arrangement  of  school-rooms  ? 


HYGIENE    OF    THE    NERVOUS    SYSTEM.  8~  i) 

ive  mistake  if  there  is  not  a  greater  improvement,  in  n  given 
time,  in  such  a  school,  than  where  there  is  an  apparent  dis- 
regard to  the  pleasure  or  comfort  of  the  scholars. 

2d.  Mechanics'  shops  should  receive  as  much  attention, 
relative  to  their  situation,  light,  warmth,  &c.,  as  school-rooms. 
If  these  are  duly  observed,  the  nervous  influence  transmitted 
from  the  brain  to  the  muscles  will  be  more  stimulating,  as  well 
as  more  abundant ;  consequently,  labor  will  be  performed  with 
less  exhaustion. 

838.  Repetition  is  necessary  to  make  a  durable  impression 
on  the  mind.     kfc  The  necessity  of  judicious  repetition  in  men- 
tal  and   moral  education,  is,  in  fact,  too  little   adverted   to, 
because  the  principle  which  renders  it  efficacious  has  not  been 
understood.     To  induce  facility  of  action  in  the  organs  of  the 
mind,  practice  is  as  essential  as  it  is  in  the  organs  of  motion. 

839.  "  In  physical  education  we  are  aware  of  the  advantages 
of  repetition.     We  know  that  if  practice  in  dancing,  fencing, 
skating,  and  riding,   is    persevered    in  for  a  length  of  time 
sufficient  to  give  the  muscles  the  requisite  promptitude  and 
harmony  of  action,  the  power  will  be  ever  afterward  retained, 
although  little  called  into  use  ;  whereas,  if  the  muscles  have 
not  been  duly  trained,  we   may  reiterate  practice  at  different 
intervals,  without  proportionate  advancement.    The  same  prin- 
ciple applies  equally  to  the   moral  and  intellectual  powers, 
because  these  operate  by  means  of  material  organs. 

840.  "  According  to  this  principle,  it  follows,  that  in  learn- 
ing a  language  or  science,  six  successive  months  of  applica- 
tion will  be  more  effectual  in  fixing  it  in  the  mind  and  mak- 
ing it  a  part  of  its  furniture,  than  double  or  treble  the  time, 
if  the  lessons  are  interrupted  by  long  intervals.     Hence  it  is 
a  great  error  to  begin  and  study,  and  then  break  off,  to  finish 


Of  mechanics' shops  ?  838.  Is  repetition  necessary  to  make  a  dm  able 
impulsion  on  the  mind?  Why?  839.  How  is  it  with  physical  educa- 
tion :  810.  What  follows,  according  to  this  principle  : 


37()  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE, 

at  a  later  period.     The  fatigue  is  thus  doubled,  and  the  suo 
cess  greatly  diminished. 

841.  t;The  best  way  is  to  begin  at  the  proper  age,  and  to 
persevere  till  the  end  is  attained.     This  accustoms  the  mind 
to  sound  exertion,  and  not  to  jits  of  attention.     Hence  the 
evil  arising  from  long  vacations ;  and  also  the  evil  of  beginning 
studies  before  the  age  at  which  they  can  be  understood,  as  in 
teaching  children  the  abstract  rules  of  grammar,  to  succeed 
in  which,  implies  in  them  a  power  of  thinking,  and  an  amount 
of  general  knowledge,  which  they  do  not  possess." 

842.  The   skull   is  susceptible   of  fractures  from   slight 
bhws.     This  occurs  most  frequently  when  the  blow  is  given 
on   the    side    of  the  head   above    and    anterior   to   the  ear. 
Here  the  bone  is  very  thin,  and  often  quite  brittle.     For  these 
jeasons,  no  instructor,  or  any  person,  should  punish  a  child  by 
striking  upon  any  portion  of  the  head. 

Observation.  A  few  years  since,  a  teacher  in  one  of  the 
ivliddle  States  gave  a  pupil  a  slight  blow  upon  the  head.  It 
fractured  the  skull  and  ruptured  a  blood-vessel  of  the  brain, 
causing  a  loss  of  consciousness,  and  finally  death. 

843.  Concussion  of  the  brain  may  be  produced  by  Hows,  or 
by  violently  shaking  a  person.     As  the  brain  is  of  pulpy  con- 
sistence, the  atoms  of  which  it  is  composed,  and  the  circula- 
tion of  blood  in  its  minute  vessels,  may  be  disturbed  by  the 
vibration  from  a  blow  on  the  exterior  of  the  skull-bones.    This 
disturbance  of  the  cerebral  organ  is  attended  with  unpleasant 
sensations,    dizziness,  loss    of    memory    and    consciousness. 
These  may  be  followed  by  headache  and  inflammation  of  the 
brain.     Concussion  of  the  brain,  and  the  results  above  men- 
tioned, may  be  produced  by  the   sudden  motion  attendant  on 
the  violent  shaking  of  a  scholar.     Consequently,  a  child  should 

841.  Wh  it  is  the  best  way  of  learning  the  sciences  ?  842.  Why  should 
not  a  child  be  struck  upon  any  portion  of  the  head  ?  What  observation 
in  this  connection  ?  843.  How  may  concussion  of  the  brain  be  produced  ? 
What  is  the  effect  of  each  upon  the  brain  of  the  child  ? 


im.iKISE    OF    THE    NKRVOUS    SYSTF.M.  *>77 

never  be  seized  by  the  arm  and  shaken  violently  as  a  method 
of  chastisement. 

Observation.  Most  persons  have  experienced  a  disagree- 
able sensation  and  dizziness,  caused  by  falling  from  a  slight 
elevation,  or  by  jumping  from  a  carriage.  This  is  the  result 
of  a  moderate  concussion  of  the  brain. 

844.  In  injuries   of  the  brain,  from  blows    and  falls,  the 
symptoms  are  usually  alarming,  and  all  should  possess  some 
information  for  such  contingencies.     In   general,  such  acci- 
dents are  attended  by  insensibility  ;  the  skin  and  extremities 
are  pale  and  cold,  the  pulse  is  very  weak  and  feeble,  and  the 
circulation  is  less  vigorous  ;  the  respiration,  also,  is  less  fre- 
quent and  full. 

845.  When  these  symptoms  exist,  the  individual,  in    the 
first  instance,  should  be  placed  in  pure  air,  and  friction  and 
dry  warmth   should  be  applied  to  the  pallid  and  cold  skin. 
This  should  be  assiduously  persevered  in  until  heat  and  color 
are  restored  to  the  skin  and  limbs,  and  due  action  of  the  heart 
and  arteries  has  been  established.     Mild  stimulants  may  alsc 
be  used  internally,  with  much  advantage.     The  sympathizing 
friends  should  not  be  permitted  to  stand  about  the  patient,  as 
they  vitiate  the  air.     There  should  be  no  bleeding  until  the 
skin  and  extremities  become  warm.    Send  for  a  surgeon  with- 
out delay. 

Give  an  instance  where  moderate  concussion  of  the  brain  is  produced. 
844.  What  are  the  symptoms  when  the  brain  is  injured  from  blows  and 
fails  ?  845.  What  treatment  should  be  adopted  ? 

32* 


*  i.- 

378  ANATOMY^    PHYSIOLOGY,    AND    HYGIENE. 

* 


CHAPTER    XLI. 

THE    SENSE    OF    TOUCH. 

846.  SENSATION  is  the  perception  of  external  ob_3Cts  by 
means  of  the  senses.     There  are  five  senses,  nan.ely,  Touch. 
Taste,  Smell,  Hearing,  and  Vision. 

847.  TOUCH  is  the  sense  by  which  the  mind  becomes  ac- 
quainted with  some  of  the  properties  of  bodies,  and  enables 

is  to  determine  whether  their  surfaces  are  smooth  or  rough, 
heir  relative  temperature,  and,  to  a  certain  degree,  their  form 
»nd  weight. 

848.  Some  physiologists  make  a  distinction  between  the 
sen&e  of  touch  and  tact.     Tact,  or  feeling,  is  more  general, 
extending  over  the  whole  surface   of  the  skin  and  mucous 
membranes,  while  touch  exists  chiefly  in  the  fingers  of  man 
and  in  the  noses  of  certain  quadrupeds. 

849.  "  In  the  exercise  of  these  functions,  tact  is  considered 
passive  ;  as,  when  any  part  of  the  system  comes  into  contact 
with  another  body,  a  sensation  of  its  presence  is  given,  with- 
out the  exercise  of  volition.     On  the  contrary,  touch  is  active, 
ind  is  exercised  voluntarily,  for  the  purpose  of  conveying  to 
.he  mind  a  knowledge  of  the  qualities  or  properties  of  the 
surfaces  of  bodies  ;  as  when  we  feel  of  a  piece  of  cloth  to 
ascertain   its   qualities,  or   a   polished   surface,  to  prove   its 
smoothness." 

850.  In  man,  the  hand  is  admirably  adapted  to  the  exercise 

846.  Define  sensation.  How  many  senses  have  we  ?  847 — 851.  What  is 
taid  of  the  sense  of  touch?  847.  Define  touch.  848.  What  is  the  difference 
between  touch  and  tact  ?  849.  In  the  exercise  of  these  functions,  which  is 
active,  and  which  passive?  850.  Why  is  the  hand  so  admirably  adapted 
to  the  exercise  of  the  sense  of  touch  ? 


HYGIENE    OF    THE    SEiNSK    O 

of  touch.  "  The  fineness  of  the  skin,  its  great 
species  of  cushion  formed  by  the  sub-cutaneous  fat  at  the 
extremities  of  the  fingers,  the  length  and  flexibility  of  these 
organs,  and  the  capability  of  opposing  the  thumb  to  the  fingers, 
like  a  pair  of  forceps,  are  so  many  conditions  essentially  favor- 
able to  the  delicacy  of  this  sense,  and  enable  us  to  appreciate 
with  exactitude  the  qualities  of  the  bodies  we  may  feel." 

851.  The  nerves  that  supply  the  sense  of  touch,  proceed 
from  the  anterior  half  of  the  spinal  cord.     Where  this  sense 
is  most  acute  and  delicate,  we  find  the  greatest  number  of 
sensitive  nervous  filaments,  and  those  of  the  largest  size. 

Observation.  In  amputating  limbs,  and  other  surgical  oper- 
ations, the  division  of  the  skin  causes  more  pain  than  all  the 
subsequent  steps  of  the  operation,  however  protracted.  The 
muscles,  cellular  membrane,  and  fat  have  but  little  sensibility ; 
while  the  bones,  tendons,  and  ligaments  are  insensible  when 
not  diseased,  and  may  be  cut  without  causing  pain. 

HYGIENE    OF   THE    SENSE    OF    TOUCH. 

852.  The  sense  of  touch  varies  in  different  persons,  and 
also  in  individuals  of  different  ages.     Thus  the  sensibilities  of 
the  child  are  more  acute  than  those  of  the  aged.     Although 
there  is  an  original  difference  of  sensibility  from  organization, 
still,  the  function  of  the  nerves  of  sensation  is  modified  by 
certain  influences. 

853.  The  healthy  or  unhealthy,  active  or  inactive  state  of 
the  brain,  influences  the  action  of  the  sensitive  nerves.     In 
sound  and  perfect  sleep,  the  brain  is  inactive.     In  this  state, 
ordinary  impressions  made  upon  the  skin  are  not  observed  by 
the  sleeping  person.     Thus  the  arm  may  be  blistered  whi'e 

851.  From  what  do  the  nerves  proceed  that  supply  this  sense  ?  852 — 
8C>4.  Give  the  hygiene  of  the  sense  of  touch.  852.  Does  this  sense  vary  in 
different  persons  ?  853.  Mention  a  condition  of  the  brain  that  influence* 
the  nerves  of  sensation. 


380  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

sleeping,  when  exposed  to  the  warm  rays  of  the  sun,  and  the 
individual  will  not  be  aware  of  it  at  the  time. 

854.  If  there  is  compression  of  the    brain,  as  when  the 
skull-bones  are  depressed,  or  disease  of  this  organ  exists,  as 
in  severe  typhus  fever,  impressions  made  upon  the  nerves  of 
the  skin  will  not  be  noticed.      The  same  is  true  when  the 
mind  is  engaged  in  intense  thought  or  study ;  heat  or  cold  may 
be  so  intense  as  to  disorganize  the  skin,  and  not  to  be  noticed. 

855.  The  varying  health  or  condition  of  the  brain  usually 
depresses  or  increases  the  sensitiveness  of  the  skin.     This  is 
seen  in  grief  and  fear,  which  diminish,  while  hope  and  joy 
increase  the  impressibility  of  this  tissue.     It  is  not  uncommon 
to  see  the  unfortunate   insane  endure  exposure  to  heat  and 
cold  with  seeming  impunity;  whereas  it  would  induce  almost 
insupportable   suffering   to  the  sane  man.     Diseases   of  the 
heart,  stomach,  and  lungs,  alter  the  condition  of  the  brain, 
and  modify,  to  a  greater  or  less  degree,  the  sensitiveness  of 
the  skill. 

856.  The  state  of  the  conducting  nervous  trunks  influences 
the  nerves  of  sensation.     If  a  nervous  trunk  is  compressed  or 
divided,  the    parts   supplied    by  nervous   filaments  from  this 
branch,  will  be  insensible  to  the  impressions  made  upon  them, 
and  consequently  such  impressions  are  not  transmitted  to  the 
brain. 

Observation.  When  the  inside  of  the  arm  or  lower  extrem- 
ities rests  upon  a  hard  surface,  the  nerves  may  be  compressed 
so  as  to  deprive  the  parts  of  sensibility.  This  condition  ia 
called  "  numbness." 

857.  The  quantity  of  Hood  supplied  to  the  skin  modifies 


854.  Mention  other  conditions  that  affect  these  nerves.  855.  What  is 
the  effect  of  the  varying  health  or  condition  of  the  brain  upon  the  sensi- 
tiveness of  the  skin  ?  Give  instances  of  this  effect.  856.  What  is  the 
result  if  a  nervous  trunk  is  divided  or  compressed  ?  How  may  "  numb- 
ness "  in  the  limbs  be  produced  >  857  Does  the  quantity  of  blood  supplied 
to  the  skin  aifect  its  sensibility  ? 


HYGIENE  OF  THE  SENSE  OF  TOUCH.         381 

its  sensitiveness.  If  the  quantity  of  blood  is  diminished,  the 
sensibility  of  the  skin  will  be  impaired.  This  is  demonstrated 
by  noting  the  effects  of  cold  upon  the  cutaneous  tissue,  the 
application  of  which  contracts  the  blood-vessels,  and  drives  the 
circulating  fluid  from  this  membrane,  which  is  shown  by  the 
paleness,  as  well  as  by  the  shrivelled  appearance  of  the  skin. 
And,  if  this  tissue  is  wounded  while  under  the  influence  of 
cold,  but  little  pain  will  be  felt,  and  this  chilling  influence  may 
be  carried  so  far  as  not  only  to  deprive  the  part  of  sensation, 
but  of  vitality. 

858.  The  influence  of  the  blood  upon  the  sensibility  of  the 
skin,  is  further  demonstrated  by  the  pain  experienced  when 
chilled  extremities  are  suddenly  exposed  to  heat.     The  nerves, 
by  the  sudden  dilatation  of  the  contracted  blood -vessels,  are  put 
in  vivid  and  rapid  motion,  which  causes  the  painful  and  tingling 
sensation  that  we  experience.     In  every  part  of  the  system, 
sudden  changes  produce  unpleasant  sensations,  and  frequently 
a  diseased  condition  of  the  organs. 

Observation.  When  the  hands,  or  other  portions  of  the 
body,  are  frozen,  or  severely  chilled,  safety  and  comfort  de- 
mand that  circulation  be  restored  to  the  parts  by  moderate 
exercise  in  a  cool  room.  Not  unfrequently,  the  vitality  of  the 
limb  is  destroyed  by  immersing  it  in  hot  water  or  holding  it 
near  the  fire. 

859.  The  quality  of  the  Mood  also  influences  sensation.     If 
the  brain  and  other  parts  of  the  nervous  .«vstem  receive  impure 
blood,  their  energy  is  depressed,  and  the  sensibility  of  the  skin 
rendered  more  or  less  obtuse. 

860.  The  condition  of  the  cuticle  modifies  the  impression 
made  upon  the  cutaneous  nerves.     1st.  When  the  cuticle  has 

How  is  it  demonstrated  ?  858.  How  is  the  influence  of  the  blood  upon 
the  skin  further  demonstrated  ?  How  should  circulation  be  restored  to 
limbs  frozen  or  severely  chilled  ?  What  should  be  avoided  ?  859.  Show 
how  the  quality  of  the  blood  influences  sensation.  860.  Give  the  1st  condi 
ti'.n  of  the  cuticle  that  influences  the  impressions  made  on  the  cutaneous 


H82  ANATOMY,    PHYSIOLOGY,  AND    HYGIENE. 

become  thick  and  hard,  like  horn,  as  on  the  inside  of  the 
mason's  hand,  it  enables  him  to  ply  his  tools  without  much 
suffering,  because  the  thickened  cuticle  diminishes  the  impres- 
sions made  upon  the  nerves. 

861.  2d.  When  the  cuticle  is  very  thin  and  delicate,  as  on 
the  hand  of  the  lady  who  is  unaccustomed  to  manual  labor.    Let 
her  pursue  some  manual  employment  for  several  hours,  and 
the  extreme  tenuity,  or  thinness  of  the  cuticle,  will  not  protect 
the   nerves   and   parts   below  from   becoming   irritated   and 
inflamed. 

862.  3d.  When  the   cuticle   is   removed  by  blistering   or 
abrasion,  the  pain  indicates   that  the  naked   nerves   are  too 
powerfully   stimulated    by   the   contact   of    external    bodies. 
4th.  When  the  cuticle  is  coated  with  impurities,  blended  with 
the  secretion  from  the  oil-glands,  the  sensibility  of  the  skin 
is  lessened. 

863.  The  sensibility  of  the  cutaneous  nerves  is  modified  ly 
being  habituated  to   impressions.     If,  for  example,  an  indi- 
vidual should  immerse  his  feet  in  moderately  warm  water,  at 
first  it  might  induce  a  smarting  sensation ;  in  a  short  time,  the 
nerves  would  not  only  become  habituated  to  tht  warm  water, 
but  its  warmth  might  be  considerably  increased.     The  same 
results  follow,  if  an  individual  is  exposed  to  a  cold  element. 
The  impressions  at  first  are  highly  disagreeable  ;  but  as  soon 
as  the  nerves  become  accustomed  to  the  surrounding  atmos- 
phere, it  may  impart  the  most  agreeable  sensations. 

Illustration.  1st.  Let  a  person  from  the  tropical  regions  go 
to  a  colder  climate,  and  the  cool  mornings  of  the  latter  will  at 
first  affect  him  unpleasantly  ;  but,  after  a  few  days'  exposure 
to  the  cooler  air,  the  sensation  will  be  far  from  disagreeable. 

2d.  Let  a  person  enter  a  room  moderately  heated  ;  grad- 
ually increase  the  temperature,  until  it  attains  extreme  sum- 

861.  The  2d  condition.  862.  The  3d  and  4th  condition.  863.  Showlum 
habit  influences  the  sensibility  of  the  cutaneous  nerves.  Give  illustration 
1st.  Illustration  2d. 


HYGIENE  OF  THE  SENSE  OF  TOUCH.         883 

mer  heat ;  not  only  the  cutaneous  nerves,  but  tne  whole 
system,  become  habituated  to  the  high  temperature.  From 
ihese  facts  we  learn  that  the  sensations,  are  not  always  a  correct 
index  of  the  real  temperature.  A  well-adjusted  thermometer 
will  indicate  it  with  unerring  certainty. 

864.  Touch  is  modified,  in  a  high  degree,  by  education. 
Thus  the  blind,  whose  "  windows  of  the  soul  "  are  closed  ti/ 
Ihe  beauties  of  the  external  world,  cultivate  this  sense  to  such 
a  degree  that  they  can  distinguish  objects  with  great  accuracy. 
And  the  rapidity  with  which  they  read  books  prepared  for 
their  use,  is  a  convincing  proof  of  the  niceness  and  extent  to 
which  the  cultivation  of  this  sense  can  be  carried. 

Illustrations.  1st.  The  cloth-dresser,  by  the  aid  of  this 
sense,  distinguishes  the  quality,  as  well  as  the  slightest  differ- 
ence of  texture,  in  the  different  pieces  of  cloth. 

2d.  The  miller,  from  a  similar  education,  quickly  detects  the 
quality  of  flour  or  meal,  by  permitting  it  to  pass  between  his 
fingers.  The  difference  in  the  texture  of  cloths,  or  the  quality 
of  the  flour,  would  not  be  distinguished  by  an  individual  whose 
tactile  sense  had  not  been  trained  to  make  nice  comparisons. 


864.  Is  this  sense  susceptible  of  improvement  ?    What  persons  cultivate 
it  to  a  high  degree  ?    Give  illustration  1st.     Illustration  2d. 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


CHAPTER    XLII. 

SENSE    OF    TASTE. 

865.  THE  chief  organ  of  TASTE  is  the  upper  surface  of  the 
tongue ;  though  the  lips,  the  palate,  the  internal  surface  of 
the  cheeks,  and  the  upper  part  of  the  oesophagus,  participate 
in  this  function. 

ANATOMY  OF  THE  ORGANS  OF  TASTE. 

866  The  tongue  is  a  double  organ,  composed  chiefly  of 
muscular  fibres,  which  run  in  almost  every  direction.  The 
two  sides  are  so  perfectly  distinct,  that  sometimes,  in  paralysis, 
one  side  is  affected,  while  the  function  of  the  other  remains 
perfect.  It  possesses  great  versatility  of  motion,  and  can  be 
moulded  into  a  great  variety  of  shapes.  In  articulation, 
mastication,  and  deglutition,  the  tongue  is  an  auxiliary  to 
other  organs. 

867.  This  organ  is  abundantly  supplied  with  blood-vessels, 
having  a  large  artery  sent  to  each  side  of  it.  It  is  also  very 
largely  furnished  with  nerves ;  it  receives  nervous  filaments 
from  the  fifth,  ninth,  and  twelfth  pairs  of  nerves.  The  branch 
of  the  fifth,  called  the  gustatory,  is  the  nerve  of  taste  and 


865.  What  is  the  chief  organ  of  taste  ?  What  other  parts  participate 
in  the  function  ?  866 — 870.  Give  the  anatomy  of  the  organs  of  taste. 
866.  Give  the  structure  of  the  tongue.  867.  Is  this  organ  abundantly 
supplied  with  blood?  From  what  source  does  the  tongue  derive  its 
nerves  ? 


ANATOMY  OF  THE  ORGANS  OF  TASTE.        385 

sensibility;*  the  twelfth,  called  the  hypo-glossal,  of  voluntary 
motion.  By  means  of  the  ninth,  called  the  glosso-pharyngeal 
the  tongue  is  brought  into  association  with  the  fauces,  oesoph- 
agus, and  larynx.  It  is  of  obvious  importance  that  these 
parts  should  act  in  concert :  and  this  is  effected  by  the  distri- 
bution of  this  nerve. 

Fig.  134. 


Fig.  134.  A  view  of  one  side  of  the  neck,  showing  the  nerves  of  the  tougm 
1,  A  fragment  of  the  temporal  bone.  2,  3,  4,  6,  7,  8,  9,  10,  11,  12,  Muscles  of  tna 
tongue,  fauces,  and  neck.  5,  The  tongue.  13,  The  common  carotid  artery.  14,  Th<? 
jugular  vein.  15,  The  external  carotid.  16,  The  internal  carotid.  17,  The  gustatory 
brunch  of  the  fifth  pair  of  nerves.  20,  The  glosso-pharyngeal  nerve.  21,  The  hypo- 
glossal,  or  the  muscular  nerve  of  the  tongue.  24,  The  pneumogastric  nerve.  25,  The 
facial  nerve. 

868.    The  surface  of  the  tongue  is  thickly  studded  with 


*  Some  physiologists  impute  the  sense  of  taste  to  the  ninth  pair 
of  nerves ;  others,  to  the  twelfth  pair ;  while  others,  again,  contend 
that  taste  is  the  result  of  a  concurrent  action  of  the  fifth,  ninth,  and 
twelfth  pairs  of  nerves. 


;8     What    is  the   nppeanincp  of  the   surface  of  the  tut.gue  ?     Explain 

134. 


386  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

fine  papillse,  or  vil'li,  which  give  the  organ  a  velvety  appear- 
ance. These  papillae  are  of  three  varieties.  The  first  is 
situated  near  the  base  of  the  tongue.  They  belong  to  the 
class  of  mucous  follicles.  They  are  larger  than  the  others, 
and  are  called  len-tic'u-lar,  from  being  shaped  like  a  lens. 
These,  together  with  the  tonsils,  (sometimes  called  the  almonds 
of  the  ears,)  secrete  mucus,  to  lubricate  the  food  in  the  act 
of  deglutition. 

869.  The  instruments  of  taste  are  the  two  other  sets  of 
papillae.     One  set  consists  of  small,  oval-shaped  bodies,  which 
are  scattered  over  the  whole  surface  of  the  tongue.     They 
give  it  a  rough   appearance,  and  are   called  the  fill-form 
papillae. 

870.  The  other  set  of  papillae  is  called  the  fun' gi-form. 
They    are    larger   than   the    former,    and   consist    of   small, 
rounded  heads,  supported  on  short  stalks,  something  in  the 
shape  o.     *  -  shrooms,  from  which  they  derive  their  name. 
In  the  last  two  described  sets  of  sensitive  papillae,  the  gustatory 
branch  of  the  fifth  pair  of  nerves  ramifies. 

Observation.  By  applying  strong  acids,  as  vinegar,  to  the 
tongue,  with  a  hair  pencil,  these  points  will  become  curiously 
lengthened. 

PHYSIOLOGY  OF  THE  OKGANS   OF  TASTE. 

871.  TASTE  is  the  sense  which  makes  us  acquainted  with 
the  savor  of  substances.      When  fluids  are  taken  into  the 
mouth,  the  papillae  dilate  and  erect  themselves,  and  the  par- 
ticular impression  excited  is  transmitted  to  the  brain  through 


How  many  varieties  of  papillae  ?  Describe  the  first  variety.  What 
is  the  function  of  the  lenticular  papillae  ?  869.  Describe  the  filiform 
papillae.  870.  The  fungiform  papillae  ?  What  nerve  ramifies  in  the  fun- 
giform  papillae  ?  How  can  these  papillae,  or  points,  be  seen  ?  871 — 875 
Give  the  physiology  of  the  organs  of  taste.  871.  Define  taste. 


PHYSIOLOGY    OF    THE    ORGANS    OF    TASTE.  387 

filaments  of  the  gustatory  nerve.  This  sense  is  closely 
connected  with  that  of  smell.  The  pleasures  derived  from 
it  are  strictly  sensual  and  corporeal,  and  contribute  in  no 
v.ay  to  the  expansion  of  the  mind,  like  those  of  hearing  and 
seeing. 

872.  If  dry,  solid   food  is  taken,  the  tongue  carries  it  to 
the  back  side  of  the  mouth,  where  it  receives  secretions  from 
the  salivary  glands ;   the  salivav  becoming  impregnated  with 
its  flavor,  flows  over  the  sides  of  the  tongue,  and  gives  to  the 
papillce  a   perception  of  the  savory  juice ;  this  impression  is 
then  communicated  to  the  brain.- 

Observation.  It  is  supposed  that  the  salts  which  enter  into 
ihe  composition  of  the  saliva,  are  very  efficient  agents  in 
reducing  substances  to  a  proper  state  for  making  impressions 
on  the  nerves  of  taste.  The  fact  that  metals  impart  a  peculiar 
taste,  is  owing  to  a  galvanic  shock,  and  not  properly  to  vrhat  we 
understand  by  taste. 

873.  The  primary  use  of  taste  is  to  guide  animals  in  the 
selection  of  food,  and  to  warn  them  against  the  introduction 
of  noxious  articles  into  the  stomach.     In  all  the  inferior  ani- 
mals, we  see  that  the  original  design  of  taste  is  still  answered. 
But   in  man,  this  sense  has  been  so  abused  and  perverted,  by 
the  introduction  of  stimulants  and  condiments,  and  the  end- 
less admixture  of  different  articles  of  food,  that  the  simple 
action  of  this  part  seems  to  have  been  superseded  almost 
entirely  by  acquired  taste. 

874.  In  children,  this  sense   is  usually  acute,  and  their 
preference  is  for  food  of  the  mildest  character.     And  it  is 
also  true,  that  every  person  has  some  peculiarities  of  taste, 


With  what  sense  is  this  closely  connected?  What  is  said  of  this 
sense  ?  872.  Give  the  process  by  which  we  taste  substances.  How  can  we 
account  for  the  taste  of  metals  when  applied  to  the  tongue  ?  873.  What 
is  the  primary  use  of  taste  ?  Where  do  we  see  it  perverted  ?  874.  How 
is  this  sense  in  children  ?  What  is  true  of  every  person  in  reference  to 
taste? 


3S8  AJN'ATl/MY,    PHYSIOLOGY,    AJND   -HYGIENE. 

or  dislikes  to  particular  articles  of  food.  This  may  bo  either 
constitutional  or  from  the  influence  of  association. 

Observation.  This  sense  has  been  made  to  vary  more  than 
any  other  by  the  refinements  of  social  life.  Thus,  the  Indian's 
like  or  dislike  to  particular  kinds  of  food,  generally  extends 
to  every  person  of  the  same  tribe  ;  but  among  civilized  men, 
no  two  individuals  can  be  found  alike  in  all  their  tastes. 

875.  This  sense  is  modified  by  habit,  and  not  unfrequently 
those  articles,  which  at  first  were  disgusting,  become  highly 
agreeable  by  persevering  in  the  use  of  them.  By  cultiva- 
tion, this  sense  may  be  made  very  acute.  Those  persons 
whose  business  leads  them  to  judge  of  the  quality  of  an 
article  by  their  taste,  can  discriminate  shades  of  flavor  not 
perceivable  by  ordinary  persons.  Epicures,  and  tasters  of 
wines  and  teas,  afford  examples. 

Observation.  Many  persons  impair  their  taste  by  bad 
habits,  as  chewing  and  smoking  tobacco,  and  using  stimu- 
lating drinks,  and  pungent  condiments  with  the  food.  These 
indulgences  lessen  the  sensibility  of  the  nerve,  and  destroy 
the  natural  relish  for  food. 

What  is  true  of  the  Indian  ?    875.  Is  this  sense  modified  by  habit  ?    Give 
instances.    How  is  this  sen»3  sometimes  impaired  ? 


ANATOMY    OF    THE    ORGANS    OF    SMELL.  389 

CHAPTER     XLIII. 

SENSE    OF    SMELL. 

876.  THIS  sense  is  located  in  the  air-passages  of  the  Nose. 
To  understand  the  function  of  smell,  the  structure  of  the  nose 
and  nasal  cavities,  with  the  distribution  of  the  olfactory  nerves, 
must  be  first  examined. 

ANATOMY  OF  THE  ORGANS  OF  SMELL. 

877.  The  NOSE  is  composed  of  the  Bones,  Fi'bro-car'ti- 
lages,  and  Mtt'cous  Mem'brane,  together  with  its  integuments. 

878.  The  BONES  of  the  nose  are  the  nasal,  and  the  nasal 
processes  of  the  upper  jaw. 

879.  The  FIBRO-CARTILAGES  give  form  and  stability  to  the 
framework  of  the  nose,   providing  at  the  same  time,  by  their 
elasticity,  against  injuries.     They  are  five  in  number. 

880.  The  MUCOUS  MEMBRANE,  which  «lines  the  interior  of 
the  nose,  is  continuous  with  the  skin  externally,  and  with  the 
lining  membrane  of  the  parts  of  the  throat.     The  entrance  of 
the  nostrils  is  provided  with  numerous  hairs,  which  serve  as 
guardians  to  the  delicate  membrane  of  the  nose. 

881.  The  NASAL  rossjs,or  nostrils,  are  two  irregular,  com- 
pressed cavities,  extending  from   the  nose  to  the  pharynx. 
These  cavities  are  bounded  superiorly  by  the  sphenoid  and 


876.  "Where  is  the  sense  of  smell  located  ?  877 — 884.  Give  the  anatomy 
of  the  organs  of  smell.  877.  Name  the  parts  that  enter  into  the  structure 
of  the  nose  ?  878.  What  bones  form  the  framework  of  the  nose  ? 
879.  What  is  the  use  of  the  cartilages  ?  880.  What  relation  has  the 
mucous  membrane  with  other  membranes  of  the  nose  ?  881.  Describe 
thi;  nasal  cavities. 

3IJ* 


390  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE 

ethmoid  bones  ;  inferiorly,  by  the  hard  palate.  In  the  middle 
line  they  are  separated  from  each  other  by  a  bony  and  fibro- 
cartilaginous  septum ;  upon  the  outer  wall  of  each  fossa,  in 
the  dried  skull,  are  three  projecting  processes,  termed  spongy 
bones.  In  the  fresh  fossa,  these  are  covered  by  a  mucous 
membrane. 

882.  The  space  that  intervenes  between  the  superior  and 
middle  spongy  bone,  is  called  the  superior  me-a'tus,  or  chan- 
nel ;  the  space  between  the  middle  and  inferior  bone,  is  the 
middle  meatus ;  and  that  between  the  inferior  bone  and  the 
floor  of  the  fossa,  is  the  inferior  meaius. 

Fig.  135. 


Fig.  135.  A  vertical  section  of  the  middle  part  of  the  nasal  cavities.  7,  The 
middle  spongy  bones.  8,  The  superior  part  of  the  nasal  cavities.  10,  The  inferio- 
spongy  bones.  11,  The  vomer.  12,  The  upper  jaw.  13.  The  middle  channel  of  the 
nuse.  14,  The  lower  channel  of  the  nose.  17,  The  palatine  process  of  the  upper  jaw- 
bone. 18,  The  roof  of  the  mouth  covered  by  mucous  membrane.  19,  A  section  of 
this  membrane. 

883.  The  MEATUSES  are  passages  that  extend  backward,  from 
the  nostrils,  into  which  are  several  openings.  They  are  lined  by  a 
mucous  membrane,  called  the  pi-tu'i-ta-ry,  or  schneiderian,  from 

882.  What  terms  are  applied  to  the  spaces  between  these  processes  ? 
What  does  fig.  135  represent  ?  883  Define  the  mcatuses.  By  what  are 
.hey  lined  ? 


PHYSIOLOGY  OF  THE  ORGANS  OF  SMELL.       39 J 

Schneider,  who  first  showed  that  the  secretion  of  the  nasal 
fossae  proceeded  from  the  mucous  membrane,  and  not  from 
the  brain. 

884.  Upon  the  mucous  membrane  of  the  nasal  passages, 
the  olfactory  nerve  ramifies,  and  also  a  branch  of  the  fifth 
pair  of  nerves.  This  membrane  is  of  considerable  extent  in 
man  ;  and  in  those  animals  whose  sense  of  smell  is  very 
acute,  it  is  still  more  extensive. 

Fig.  136. 


Fig.  136.  A  side  view  of  the  passage  of  the  nostrils,  and  the  distribution  of  tha 
olfactory  nerve.  4,  The  olfactory  nerve.  5,  The  fine  arid  curious  divisions  of  this 
nerve  on  the  membrane  of  the  nose.  6,  A  branch  of  the  fifth  pair  of  nerves. 


PHYSIOLOGY    OF    THE    ORGANS    OF    SMELL. 

885.  The  sense  of  smell  enables  us  to  discern  the  odor  or 
scent  of  any  thing.  When  substances  are  presented  to  the 
nose,  the  air  that  is  passing  through  the  nostrils  brings  the 
odoriferous  particles  of  matter  in  contact  with  the  filaments 
of  the  olfactory  nerves,  that  are  spread  upon  the  membrane 


884.  What  nerves  ramify  upon  this  membrane  ?  What  is  represented  by 
fig.  136  ?  885-— 899.  Give  the  physiology  of  the  organs  of  smell.  885.  How 
does  the  mind  become  sensible  of  odoriferous  particles  ? 


«H9*2  AN  ATOM  v,   riiYsior.ocv,  AND  nvniRXF. 

I  hat   lines  the  air-passages,  and  the  impression  is  then  trans- 
mitted to  the  brain. 

886.  This  sense,  with  that  of  taste,  aids  man  as  well  as  the 
inferior  animals,  in  selecting  proper  food,  and  it  also  gives  us 
pleasure  by  the  inhalation  of  agreeable  odors.     The  sense  of 
smell,  like  that  of  taste  and  touch,  may  be   improved   by  cul- 
tivation.    It  likewise  varies  in  different  persons. 

Observation.  Sometimes  this  sense  seems  to  possess  ;i 
morbid  degree  of  acuteness  in  respect  to  odors,  which  is  highly 
inconvenient  and  even  dangerous.  With  some  individuals,  the 
smell  of  certain  fruits,  flowers,  cheese,  &c.,  produce  nausea 
and  even  convulsions. 

887.  In  the  inferior  animals  generally,  the  sense  of  smell 
is  more  acute  than  in  man.     Thus  the  bloodhound  will  track 
the  hare  over  the  ground  for  miles,  guided  only  by  the  odor 
that  it  leaves  in  its  flight.     He  also  traces  the  progress  of 
his  master  through  thickly-crowded   streets,  distinguishing  his 
footsteps  from  those   of  a  thousand  others,  and    amidst  the 
odorous  particles  emanating  from  a  thousand  sources. 

Observation.  In  some  of  the  higher  orders  of  the  inferior 
animals,  there  is  an  astonishing  acuteness  of  smell  in  regard  to 
eflluvia  that  come  from  living  animals.  To  these  animals,  it 
possesses  an  importance  in  them  far  beyond  what  it  has  ip 
man,  by  making  them  acquainted  with  the  presence  of  their 
enemies  or  their  prey,  when  the  eye  and  ear  are  incapable 
of  acting.  It  is  related  by  travellers  in  Africa,  that  they  were 
always  apprised  of  lions  in  their  vicinity  during  the  night,  by 
the  moans  and  tremblings  of  their  horses. 

888.  Smell  is  somewhat  under  the  control  of  the  will.    That 


886.  What  is  the  use  of  the  sense  of  smell?  Can  this  sense  be  im 
proved  by  cultivation  ?  What  is  said  respecting  this  sense  in  some 
individuals  ?  887.  What  is  said  of  this  sense  in  the  bloodhound  ?  Men- 
tion an  instance  of  astonishing  acuteness  of  smell  in  some  of  the  higher 
orders  of  animals.  888.  Show  that  smell  is  somewhat  under  the  control 
of  the  will. 


PHYSIOLOGY  OF  THE  ORGANS  OF  SMLLL.        39? 

is,  we  have  the  power  of  receiving  or  rejecting  odors  that  are 
presented;  thus,  if  odors  are  agreeable,  we  inspire  forcibly,  to 
enjoy  them  ;  but,  if  they  are  offensive,  our  inspirations  aro 
more  cautious,  or  we  close  our  nostrils.  This  sense  is  like- 
wise modified  by  habit;  odors  which,  in  the  first  instance, 
were  very  offensive,  may  not  only  become  endurable,  but 
even  agreeable. 

889.  Acuteness  of  smell  requires  that  the  brain  and  nerve 
of  smell  be  healthy,  and  that  the  membrane  that  lines  the  nose 
be  thin  and  moist.  Any  influence  that  diminishes  the  sensi* 
bility  of  the  nerves,  thickens  the  membrane,  or  renders  it  dry, 
impairs  this  sense. 

Observations.  1st.  Snuff,  when  introduced  into  the  nose, 
not  only  diminishes  the  sensibility  of  the  nervous  filaments, 
but  thickens  the  lining  membrane.  This  thickening  of  the 
membrane  obstructs  the  passage  of  air  through  the  nostrils, 
and  thus  obliges  "  snuff-takers "  to  open  their  mouths  when 
they  breathe. 

2d.  The  mucous  membrane  of  the  nasal  passages  is  the 
seat  of  chronic  catarrh.  This  affection  is  difficult  of  removal, 
as  remedial  agents  cannot  easily  be  introduced  into  the  wind- 
ings of  these  passages.  Snuff  and  many  other  articles  used 
for  catarrh,  producp  more  disease  than  they  remove. 


889.  On  what  does  acuteness  of  smell  depend  ?    What  effect  ha°  snuff 
when  introduced  into  the  nose  ?    What  is  said  of  chronic  catarrh  ? 


394  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 


CHAPTER     XLIV. 

SENSE    OF    VISION. 

890.  THIS  sense  contributes  more  to  the  enjoyment  and 
happiness  of  man  than  any  other  of  the  senses.     By  it  we 
perceive  the  form,  color,  volume,  and  position  of  objects  that 
surround  us.     The  eye  is  the  organ  of  sight,  or  vision,  and  its 
mechanism  is  so  wonderful,  that  it  not  only  proves  the  exist- 
ence of  a  great  First  Cause,  but  perhaps,  more   than  other 
organs,  the  design  of  the  Creator  to  mingle  pleasure  with  our 
existence. 

ANATOMY    OF    THE    ORGANS    OF    VISION. 

891.  The  apparatus  of  vision  consists  of  the  Op'tic  Nerve, 
the  Globe  and  Muscles  of  the  eye,  and  its  Protecting  Organs. 

892.  The  OPTIC  NERVE  arises  by  two  roots  from  the  cen 
tral  portion  of  the  base  of  the  brain.    The  two  nerves  approach 
each   other,    as    they    proceed    forward*  and    some    of    the 
fibres  of  each  cross  to  the  nerve  of  the  opposite  side.     They 
then  diverge,  and  enter  the  globe   of  the  eyes  at  their  back 
part,  where  they  expand,  and  form  a  soft,  whitish  membrane. 

893.  The  GLOBE,  or  ball  of  the  eye,  is  an  optical  instru- 
ment of  the  most  perfect  construction.    The  sides  of  the  globes 
are  composed  of  Coals,  or  membranes.     The  interior  of  the 
globe  is  filled  with  refracting  Humors,  or  me'di-ums. 


890.  Which  sense  contributes  most  to  the  enjoyment  of  man  ?  What  do 
we  perceive  by  this  sense  ?  What  is  said  of  the  mechanism  of  the  eye  5 
891 — 916.  Give  the  anatomy  of  the  organs  of  vision.  891.  Of  what  does  iLs 
apparatus  of  vision  consist  ?  892  Describe  the  optic  nerve  893.  Describe 
the  globe  »f  the  eye. 


ANATOMY    OF    THE    ORGANS    OF    VISION.  39ft 

894.  The  COATS  are  three  in  number :  1st.  The  Scle- 
rotic and  Corrie-a.  2d.  The  Cho'roid,  Iris,  and  Cil'ia-ry 
processes.  3d.  The  Ret'i-na. 

895  The  HUMORS  are  also  three  in  number:  1st.  The 
A'que-ous,  or  watery.  2d.  The  Crys'tal-line,  (lens.)  3d.  The 
Vit're-ous,  or  glassy. 

Fig.  137; 


Fig.  137.  The  second  pair  of  nerves.  1,1,  Globe  of  the  eye  :  the  one  on  the  left 
is  perfect,  but  that  on  the  right  has  the  sclerotic  and  choroid  coats  removed,  to  show 
the  retina:  2,  The  crossing  of  the  optic  nerve.  5,  The  pons  varolii.  6,  The  me- 
dulla oblongata.  7,  8,  9,  10,  11,  12,  13,  The  origin  of  several  pairs  of  cranial  nerves 

896.  The  SCLEROTIC  COAT  is  a  dense,  fibrous  membrane 
and  invests  about  four  fifths  of  the  globe  of  the  eye.  It  gives 
form  to  this  organ,  and  serves  for  the  attachment  of  the  mus- 
cles that  move  the  eye  in  various  directions.  This  coat,  from 
the  brilliancy  of  its  whiteness,  is  known  by  the  name  of  "  the 

894.  Name  the  coats  of  the  eye.  895.  Name  the  humors  of  the  eye 
Explain  fig.  137-  896.  Describe  the  sclerotic  coat. 


)  ANATOMY,  PHYSIOLOGY,    AND    HYGIENE. 

white  of  the  eye."  Anteriorly,  the  sclerotic  coat  presents  o 
bevelled  edge,  which  receives  the  cornea  in  the  same  way  that 
a  watch-glass  is  received  by  the  groove  in  its  case. 

897.  The  CORNEA  is  the   transparent  projecting  layer,  that 
forms  the  anterior  fifth  of  the  globe  of  the  eye.     In  form,  if 
is  circular,  convexo-concave,  and   resembles  a  watch-glass 
It  is  received  by  its  edge,  which  is   sharp  and  thin,  within  the 
bevelled  border  of  the  sclerotic,  to  which  it  is  firmly  attached. 
The  cornea  is  composed  of    several    different    layers ;    its 
blood-vessels  are  so  small  that  they  exclude  the  red  particles 
altogether,  and  admit  nothing  but  serum. 

898.  The  CHOROID  COAT  is  a  vascular  membrane,  of  a  rich 
chocolate -brown  color  upon  its  external  surface,  and  of  a  deep 
black  color  within.     It  is  connected,  externally,  with  the  scle- 
rotic, by  an  extremely  fine  cellular  tissue,  and  by  the  passage ' 
of  nerves   and   vessels ;  internally,  it  is   in  contact  with   the 
retina.     The  choroid  membrane  is  composed  of  three  layers. 
It  secretes  upon  its  internal  surface  a  dark  substance,  called 
pig-ment'um  ni'grum,  which   is   of   great  importance  in  the 
function  of  vision. 

899.  The  IRIS  is  so  called  from  its  variety  of  color  in  dif- 
ferent persons.     It  forms  a  partition  between  the  anterior  and 
posterior  chambers  of  the  eye,  and  is  pierced  by  a  circulai 
opening,  which  is  called  the  pu'pil.     It  is  composed   of  two 
layers.     The  radiating  fibres  of  the  anterior  layer  converge 
from  the  circumference  to  the  centre.     Through  the  action  of 
these  radiating  fibres  the  pupil  is  dilated.     The  circular  fibres 
surround  the  pupil,  and  by  their  action  produce  contraction  of 
its  area.     The  posterior  layer  is  of  a  deep  purple  tint,  and  is 
called  u~ve'a,  from  its  resemblance  in  color  to  a  ripe  grape. 

How  are  this  coat  and  the  cornea  united  ?  897-  Describe  the  cornea. 
898.  What  is  the  color  of  the  external  surface  of  the  choroid  coat  ?  Of 
the  internal?  How  is  it  connected  externally  ?  How  internally  ?  What 
does  this  membrane  secrete  upon  its  internal  surface  ?  899.  Describe  1  he- 
iris.  Of  how  many  layers  of  fibres  is  the  iris  composed?  What  is  the 
function  of  the  radiating  iibres  ?  Of  the  circular  ? 


ANATOMY    OF    THE    ORGANS    OF    VISION.  307 

900.  The  CILIARY  PROCESSES  consist  of  a  number  of  trian- 
gular folds,  formed,  apparently,  by  the  plaiting  of  the  internal 
layer  of  the  choroid  coat.  They  are  about  sixty  in  number. 
Their  external  border  is  continuous  with  the  internal  layer  of 
rhe  choroid  coat.  The  central  border  is  free,  and  rests  against 
the  circumference  of  the  crystalline  lens.  These  processes 
are  covered  by  a  layer  of  the  pigmentum  nigrum. 

Fig.  138. 


Fig.  138.  A  view  of  the  anterior  segment  of  a  transverse  section  of  the  g!obe  r 
l**e  eye,  seen  from  within  1,  The  divided  edge  of  the  three  coats  —  sclerotic,  clio- 
i oid,  and  retina.  2,  The  pupil.  3,  The  iris :  the  surface  presented  to  view  in  tliis 
*ection  being  the  uvea.  4,  The  ciliary  processes.  5,  The  scalloped  anterior  bordt-r 
of  the  retina. 


901.  The  RETINA  is  composed  of  three  layers:  The  ex- 
ternal ;  middle,  or  nervous ;  and  internal,  or  vascular.  The 
external  membrane  is  extremely  thin,  and  is  seen  as  a  floccu- 
!ent  film,  when  the  eye  is  suspended  in  water.  The  nervous 
membrane  is  the  expansion  of  the  optic  nerve,  and  forms  a 
thin,  semi-transparent,  bluish-white  layer.  The  vascular 


900.    How  are  the  ciliary  processes  formed  ?     "What  does  fig  138  exhibit.  > 
')!.  Of  how  many  layers  is  the  retina  composed  ?     Describe  the  external 
iycr.     The  nervous  layer. 
a  I 


308  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE 

membrane  consists  of  the  ramifications  of  a  minute  artery  and 
its  accompanying  vein.  This  vascular  layer  forms  distinct 
sheaths  for  the  nervous  papillae,  which  constitute  the  inner 
surface  of  the  retina. 

902.  The  AQUEOUS  HUMOR  is  situated  in  the  anterior  and 
posterior   chambers  of  the   eye.     It  is  an  albuminous    fluid, 
having  an  alkaline  reaction.     Its  specific  gravity  is  a  very  little 
greater  than  distilled  water.     The   anterior   chamber  is  the 
space  intervening  between  the  cornea,  in  front,  and  the  iris 
and  pupil,  behind.     The   posterior   chamber   is   the  narrow 
space,  less  than  half  a  line  in  depth,  bounded  by  the  posterior 
surface  of  the  iris  and  pupil,  in  front,  and  by  the  ciliary  pro- 
cesses and  crystalline  lens,  behind.     The  two  chambers  are 
lined  by  a  thin  layer,  the  secreting  membrane  of  the  aqueous 
humor. 

903.  The  CRYSTALLINE  HUMOR,  or  lens,  is  situated  imme- 
diately behind   the   pupil,  and  is   surrounded  by  the  ciliary 
processes.     This  humor  is  more  convex  on  the  posterior  than 
on  the  anterior  surface,  and,  in  different  portions  of  the  sur- 
face of  each,  the  convexity  varies  from  their  oval  character. 
It  is  imbedded  in  the  anterior  part  of  the  vitreous  humor,  from 
which  it  is  separated  by  a  thin  membrane,  and  is  invested  by 
a  transparent  elastic  membrane,  called  the  capsule  of  the  lens. 
The  lens  consists  of  concentric  layers,  disposed  like  the  coats 
of  an  onion.     The  external  layer  is  soft,  and  each  successive 
one  increases  in  firmness  until  the  central  layer  forms  a  hard- 
ened nucleus.    These  layers  are  best  demonstrated  by  boiling, 
or  by  immersion  in  alcohol,  when  they  separate  easily  from 
each  other. 

Observations.     1st.  The  lens  in  the  eye  of  a  fish  is  round, 

The  vascular  layer.  902.  Where  is  the  aqueous  humor  situated  ?  What 
part  of  the  eye  is  called  the  anterior  chamber  ?  The  posterior  chamber  ? 
With  what  are  the  chambers  lined  ?  903.  "Where  is  the  crystalline  humor 
situated  ?  With  what  is  it  surrounded  ?  Of  what  does  the  lens  consist ' 
How  are  these  layers  best  demonstrated  ?  What  is  produced  when  the 
lens,  or  its  investing  rnombrane,  is  changed  in  structure  ? 


ANATOMY    UF    THE    ORGANS    OF    VISION.  399 

like  a  globe,  and  has  the  same  appearance,  when  boiled,  as  the 
•ens  of  the  human  eye. 

2d.  When  the  crystalline  lens,  or  its  investing  membvane, 
is  changed  in  structure,  so  as  to  prevent  the  rays  of  light  pass- 
*ng  to  the  retina,  the  affection  is  called  a  cataract. 

Fig  139 


Fig.  139.  A  section  of  the  globe  of  the  eye.  1,  The  sclerotic  coat.  2,  1  he  cornea 
(This  connects  with  the  sclerotic  coat  by  a  bevelled  edge.)  3,  The  choroid  coat 
6,  6,  The  iris.  7,  The  pupil.  8,  The  retina.  10,  11,  11,  Chambers  of  the  eye  that 
contain  the  aqueous  humor.  12,  The  crystalline  lens.  13,  The  vitreous  humor. 
15,  The  optic  nerve.  16,  The  central  artery  of  the  eye. 

904.  The  VITREOUS  HUMOR  forms  the  principal  bulk  of  the 
globe  of  the  eye.  It  is  an  albuminous  fluid,  resembling  the 
aqueous  humor,  but  is  more  dense,  and  differs  from  the  aque- 
ous in  this  important  particular,  that  it  has  not  the  power 
of  re-producing  itself.  If  by  accident  it  is  discharged,  the  eye 
is  irrecoverably  lost ;  while  the  aqueous  humor  may  be  let  out, 
and  will  be  again  restored.  It  is  enclosed  in  a  delicate  mem- 
brane, called  the  hy'a-loid,  which  sends  processes  into  the 
interior  of  the  globe  of  the  eye,  forming  the  cells  in  which 
the  humor  is  retained. 


904.  Describe  the  vitreous  humor.     How  does  this  humor  differ  from  the 
aqueous  ?     What  membrane  encloses  the  vitreous  humor  ? 


400 


ANATOMY,    PHYSIOLOGY,    AND    HYC.TF.NE. 


Observation.  The  structure  of  this  organ  can  be  seen  by 
first  freezing  the  eye  of  a  sheep  or  an  ox ;  it  then  can  be  cut 
in  various  directions,  and  each  part  separately  examined. 

905.  The  MUSCLES  of  the  eye  are  six  in  number.  They 
are  attached,  at  one  extremity,  to  the  bones  of  the  orbit  behind 
the  eye ;  at  the  other  extremity,  they  are  inserted  by  broad, 
thin  tendons,  near  the  junction  of  the  cornea  with  the  sclerotic 
coat.  The  white,  pearly  appearance  of  the  eye  is  caused  by 
these  tendons. 

Fig.  HO. 


Fig.  140.  A  view  of  the  eye  and  its  muscles,  a,  6,  c,  d,  e,  Five  of  these  muscles. 
/,  The  optic,  nerve.  G,  The  trochlea,  or  pulley  over  which  one  of  the  muscles  passes. 
The  bone  is  seen  above  and  below  the  eye. 

Observation.     If  the  external  muscle  is  too  short,  the  eye 
is  turned  out,    producing  the  "  wall    eye."     If  the   internal 

905.  How  many  muscles  has  the  eye  ?  Give  their  attachments.  What 
causes  the  pearly  appearance  of  the  eye  ?  What  does  fig.  140  represent  ? 
What  is  the  effect  if  the  external  muscle  is  contracted?  The  intoin.r 
muscle  r 


ANATOMY    OF    THE    ORGANS    OF    VISION.  403 

muscle   is   contracted,  the  eye  is   turned  inward  toward  the 
nose.     It  is  then  called  a  "  cross  eye." 

906.  The  PROTECTING  ORGANS  are  the  Or'lits,  Eyebrows 
Eyelids,  and  Lacli'ry-mal  Apparatus. 

907.  The  ORBITS   are    deep,  bony  sockets,  in   which    the 
globes  of  the  eyes  are  situated.     They  have  the  form  cf  a 
cone,  the  base  of  which  is  open  and  directed  forward.     The 
bottom  of  the  orbits  is  pierced  by  a  large  hole,  which  gives 
passage  to  the  optic  nerve.     These  cavities  are  lined  with  a 
thick  cushion  of  fat,  in  order  that  the  eyes  may  move  in  all 
directions,  with  perfect  freedom  and  without  friction. 

908.  The  EYEBROWS  are  two  projecting  arches  of  integ-i- 
ment,  covered  with  short,  thick  hairs,  which  form  the  upper 
boundary  of  the  orbits      The  eyebrows  are  so  arranged  that 
they  prevent  the  moisture  that  accumulates  on  the  forehead, 
in  free  perspiration,  from  flowing  into  the  eye,  and  also  shade 
these  organs  from  too  vivid  light. 

909.  The    EYELIDS   are  two   movable  curtains  placed   m 
front  of  the  eye.     They  have  a  delicate  skin  on  the  outside, 
muscular  fibres  beneath,  and  a  narrow  cartilage  on  their  edges, 
which  tends  to  preserve  the  shape  of  the  lid.     Internally,  they 
are  lined  by  a  smooth  membrane,  which  is  reflected  over  the 
front  of  the  eye  upon  the  sclerotica.     This  membrane  is  called 
the  con-junc-ti'va.     It  secretes  the  fluid  that  moistens  and  lubri- 
cates the  eye,  and  which  causes  the  eyelids  to  open  and  shut 
without  friction. 

Observation'.  When  the  portion  of  this  membrane  that 
is  reflected  o^er  the  globe  of  the  eye,  is  inflamed,  there  is 
frequently  a  deposition  of  whitish  material,  called  lymph.  This 
accounts  for  the  films,  opacities,  and  white  spots  seen  upon 
the  eye  after  the  inflammation  has  subsided. 

9%.  Name  the  protecting  organs  of  the  eye.  907.  Describe  the  orbits 
TIow  are  the  movements  of  the  eye  facilitated  ?  908.  Describe  the  eye- 
brows. What  does  this  arrangement  prevent?  909.  Describe  the  eyelids 
What  is  thp  u-o  of  the  conjunctiva  ?  How  are  the  white  spots  frequently 
seen  upon  the  eye  aixtr-ntevl  'oi  ? 


102  ANATOMY,    PHYSIOLOGY,   AND    HYGIENE. 

910.  There   are   found  several   small  glands   on   the    in- 
ternal surface  of  the  cartilage,  which  have  the  appearance  of 
parallel  strings  of  pearls.     They  open  by  minute  apertures 
upon  the  edges  of  the  lids.     The  secretion  from  these  glands 
prevents  the  edges  of  the  eyelids  from  being  united  during 
sleep. 

911.  The  edges  of  the  eyelids  are  furnished  with  a  triple 
row  of  long,  thick  hairs,  called  eyelashes,  which  curve  upward 
from  the  upper  lid,  and  downward  from  the  lower,  so  that 
they  may  not  interlace  with  each  other  in  the  closure  of  the 
eyelids.      These    appendages   of  the   eye,   by   closing,   not 
only    protect   it   from   moisture,  but  from   dust,  particularly 
during  sleep.     They  likewise,  by  their  movements  in  open- 
ing and  shutting,  spread  the   lubricating  fluid  equally  over 
the  eye. 

912.  The  LACHRYMAL  APPARATUS,  which  secretes  the  tears, 
consists  of  the  Lachrymal  Gland  with  its  ducts,  Lachrymal 
Canals,  and  the  Nasal  Duct. 

913.  The  LACHRYMAL  GLAND  is  situated  at  the  upper  and 
outer  angle  of  the  orbit.     It  is  about  three  quarters  of  an  inch 
in  length,  flattened  and  oval  in  shape,  and  occupies  a  depres- 
sion in  the  orbital  plate  of  the  frontal  bone.     Ten  or  twelve 
small  ducts  pass  from  this  gland,  and  open  upon  the  upper 
eyelid,  where  they  pour  upon  the  conjunctiva  the  lachrymal 
fklid,  or  tears.     This  secretion  is  maintained  while  we  are 
asleep,  as  well  as  when  we  are  awake.     The  eye  from  this 
cause  is  kept  constantly  moist. 

914.  The  LACHRYMAL  CANALS  commence  at  minute  open- 
ings upon  the  free  borders  of  each  eyelid,  near  the  internal 

910.  What  are  found  on  the  internal  surface  of  the  cartilage  of  the  eye- 
lids ?  Where  do  they  open,  and  what  is  their  use  ?  911.  With  what  are  the 
edges  of  the  eyelids  furnished  ?  What  are  their  uses  ?  912.  Of  what  does 
the  la^nrymal  apparatus  consist  ?  913.  Describe  the  lachrymal  gland 
How  many  ducts  pass  from  this  gland,  and  what  do  they  convey  to  the 
eye  ?  Why  is  the  eye  constantly  moist  *  914.  Where  do  the  lachrymal 
canals  commence  ? 


ANATOMY    OF    THE    ORGANS    OF    VISION.  -10;} 

Angle  of  the  eye,  by  two  small  orifices,  called  punc'ta  lath-ry- 
ma'li-a,  (tear  points.)  Each  of  these  points  communicate 
with  the  sac  at  the  upper  part  of  the  nasal  duct. 

915.  The  NASAL  DUCT  is  a  shoi  canal,  about  three  quarters 
of  an  inch  in  length,  directed  downward  and  backward  to  the 
inferior  channel  of  the  nose,  where  it  terminates  by  an  ex- 
panded orifice. 

Fig.  Hi. 
1 


Fig.  141.  1,  The  lachrymal  gland.  2,  Ducts  leading  from  the  lachrymal  gland  to 
the  upper  eyelid.  3,  3,  The  puncta  lachrymalia.  4,  The  nasa1  sac.  5,  The  termi- 
nation of  the  nasal  duct. 

916.  The  fluid  (tears)  secreted  by  the  lachrymal  gland,  is 
conveyed  to  the  eye  by  the  small  ducts  before  described.  It 
is  then  imbibed  by  the  puncta  lachrymalia,  and  carried  by  the 
lachrymal  canals  into  the  lachrymal  sac,  from  which  it  is 
passed  to  the  nasal  cavities  by  the  nasal  ducts. 

What  are  they  called  ?  With  what  do  they  communicate  ?  915.  De- 
Bcr:be  the  nasal  duct.  916.  How  are  the  tears  conveyed  from  the  lachrymal 
gland  to  the  nose  ? 


4tM  ANATOMY,    PHYSIOLOGY,    AND    HYGIKNE 


CHAPTER    XLV. 

PHYSIOLOGY    OF    THE    ORGANS    OF    VISION. 

917.  To  comprehend  the  theory  of  vision,  it  is  not  suffi- 
cient to  know  the  structure  of  the  eye.     We  must  be  familial 
with  some  of  the  properties  of  a  subtile  fluid,  which  is  con- 
stantly emanating  from  all  luminous  bodies,  called  light. 

918.  It  is  the  province  of  natural  philosophy,  rather  than 
physiology,  to  enter  minutely  upon   the   properties  of  light. 
It  may  be  observed,  however,  that,  when  light  passes  through 
any  medium  of  the  same   density,  the  rays  are  in  straight 
lines  ;  but,  when  it  passes  from  one  medium  into  another  of 
different  density,  it  is  refracted,  or  turned    from  a   straight 
course,    unless    it   strikes    the    medium    in    a    perpendicular 
direction  —  then   light   passes  through  without   a   change  of 
direction. 

919.  When  a  ray  of  light   meets  with  a  body,  it  either 
passes  through  it,  or  is  reflected  by  it,  or  it  may  be  absorbed. 
Again,  in  proportion  as  the  rays  of  light  become  distant  from 
the  body  from  which  they  emanate,  they  diverge  one  from 
the  other.     In  accordance  with  the  laws  of  optics,  the  rays 
of  light,  in  passing  through  an  optical  instrument  like  the  eye, 
must  cross  each  other,  and  thus  produce  an  inverted  image 
of  the  object  from  which  the  rays  proceed.     With  the  general 


917 — 933.  Give  the  physiology  of  the  organs  of  vision.  917-  What  is  neces- 
sary in  order  to  understand  the  theory  of  vision  r  918.  When  light  passes 
through  a  medium  of  the  same  density,  in  what  direction  will  he  its  rays  ? 
Of  a  different  density  ?  What  exception  ?  919.  When  light  meets  with 
a  body,  what  takes  place  ?  What  is  said  in  reference  to  rays  of  light  iu 
passing  through  the  eye  ? 


PHYSIOLOGY    OF    THE    ORGANS    OF    V1SMN.  405 

vio-w  of  the  structure  of  the  eye,  we  will  now  examine  the 
use  of  each  part  in  the  function  of  vision. 

92C.  The  sclerotic  coat  not  only  gives  form  to  the  body 
of  the  eye,  but  protection  to  the  interior  and  more  delicate 
parts.  The  choroid  coat  seems  to  be  chiefly  composed  of  u 
tissue  of  nerves  and  minute  blood-vessels ;  the  latter  give 
nourishment  to  the  different  parts  of  the  eye.  One  of  the 
uses  of  this  coat  is,  to  absorb  the  rays  of  light  Immediately 
after  they  have  passed  through  the  retina.  This  is  effected 
by  the  black  pigment  that  lines  its  inner  surface.  Were  it 
not  for  this  provision,  light  would  be  too  intense,  and  vision 
indistinct. 

Observation.  In  albinos,  where  there  is  an  absence  of  the 
black  pigment,  the  rays  of  light  traverse  the  iris,  and  even 
the  choroid  coat,  and  so  overwhelm  the  eye  with  light,  that 
their  vision  is  quite  imperfect,  except  in  the  dimness  of 
evening,  or  at  night.  In  the  manufacture  of  optical  instru- 
ments, care  is  taken  to  color  their  interior  black,  for  the  same 
object,  namely,  the  absorption  of  scattered  rays. 

921.  The  iris,  by  means  of  its  powers  of  expansion  and 
contraction,  regulates  the  quantity  of  light  admitted  through 
the  pupil.  If  the  iris  is  thin,  and  the  rays  of  light  pass 
through  its  substance,  they  are  immediately  absorbed  by  the 
uvea,  and,  if  that  layer  be  insufficient,  they  are  taken  up  by 
the  black  pigment  of  the  choroid  coat. 

Observation.  When  we  look  toward  the  bottom  of  the  eye, 
the  pupil  appears  like  a  black  spot,  instead  of  an  opening. 
This  is  caused  by  seeing  the  black  pigment  through  the  retina 
and  humors  of  the  eye. 


920.  What  is  the  use  of  the  sclerotic  coat  ?  Of  what  is  the  choroid 
coat  chiefly  composed  ?  What  is  the  use  of  this  coat :  How  is  it  effected  ? 
What  is  said  of  albinos  ?  What  care  is  taken  in  the  manufacture  of 
optical  instruments  ?  921.  What  is  the  use  of  the  iris  ?  When  we  look 
toward  the  bottom  of  the  eye,  why  does  the  pupil  lock  like  a  black  spot, 
instead  of  an  opening  ? 


4'!b  ANATOMY,    PHYSIOLOGY,    ANU    HYGIENE. 

922.  The  cornea,  and  the  aqueous,  crystalline,  and  vitreous 
humors,  are  transparent ;  so  that  rays  of  light  traverse  these 
parts  of  the  eye,  and  fall  upon  the  retina.      The  office  of 
these  humors  and  the  cornea  is  to  refract  the  rays  of  light  in 
such  proportion  as  to  direct  the  image  in  the  most  favorable 
manner  upon  the  retina. 

923.  The  office  of  the  retina  is  to  receive  the  impression 
of  the  rays  of  light  which  leave  an  object  at  which  we  look, 
and  it  is  upon  it  that  a  small  but  very  clear  image  of  that 
object  is  formed.     The  impression  thus  produced  by  the  re- 
flected light  is  transmitted  by  the  optic  nerve  to  the   brain, 
which  receives  the  sensation.     This  constitutes  vision. 

924.  The  optic  nerve  has  but  one  function,  that  of  sight. 
Sensibility  is  conferred  on  this  organ  by  a  large  branch  from 
the  fifth  pair  of  nerves,  which  ramifies  upon  the    different 
parts  of  the  eye  and  its  appendages.     These  parts,  however, 
receive  some  nervous  filaments  from  the  seventh  pair. 

Observations.  1st.  The  large  number  of  sensitive  ner- 
vous filaments  renders  the  visual  organ  very  impressible  to 
bodies  that  cause  irritation,  as  dust,  or  intense  light.  This 
compels  us  to  use  due  care  to  shield  the  eye  from  the  influ- 
ence of  agents  that  would  impair  or  destroy  vision. 

2d.  Although  particles  of  dust,  when  in  contact  with  the 
delicate  parts  of  the  eye,  induce  severe  pain,  yet  these  parts 
may  be  cut  in  surgical  operations,  and  the  patient's  sufferings 
are  not  as  great  as  when  an  incision  is  made  in  the  skin  to 
remove  a  small  tumor. 

925.  Different  degrees  of  density,  as  already  mentioned, 
modify  the  refractory  power  of  any  transparent  medium.     It 
is  found,  on  examination,  that  the  cornea,  the  vitreous,  the 


922.  What  is  the  use  of  the  cornea,  aqueous,  crystalline,  and  vitreous 
humors?  923.  What  is  the  office  of  the  retina?  924.  What  is  the 
function  of  the  optic  nerve  ?  How  is  sensibility  conferred  on  this  organ  ? 
Give  the  1st  observation  in  this  connection.  The  2d  observation. 


PHYSIOLOGY    OF    THE    ORUANS    OF    VISION. 


407 


rrystalline,  and  .he  aqueous  humors,  have  eacn,  severally, 
various  degrees  of  density :  and  that  the  crystalline  lens,  ai 
its  circumference,  is  less  dense  than  at  its  centre.  These 
circumstances  modify  the  direction  of  the  refraction  of  the 
rays  of  light,  in  their  passage  from  the  cornea  to  the  retina. 

926.  The  refracting  powers  of  the  plane,  convex,  concave, 
plano-convex,  plano-concave,  and  concavo-convex  lenses,* 
are  different.  The  cornea  and  aqueous  humors  are  convexo- 
concave,  the  vitreous  humor  is  concavo-convex,  while  the 
crystalline  humor  is  a  convexo-convex  medium.  (Fig.  139.) 


Fig.  142.  The  forms  of  the  different  lenses.  1,  A  plane  lens.  2,  A  glo*e  lens 
3,  A  convexo-convex  lens.  4,  A  plano-convex  lens.  5,  A  concavo-concave  lens 
6,  A  plano-concave  lens.  7,  Meniscus.  8,  A  concavo-convex  lens. 

927.  The  different  degrees  of  convexity  01  concavity  also 
modify  the  refracting  character  of  transparent  mediums. 
The  crystalline  lens  is  of  different  degrees  of  convexity  on 
its  two  sides.  The  convex  surfaces  of  the  aqueous  and 
vitreous  humors  are  segments  of  circles,  of  different  diame- 
ters from  their  concave  surfaces.  (Fig.  139.)  All  these 

*  The  refracting  character  of  differently-formed  lenses  is  illustrated 
in  the  works  on  Natural  Philosophy,  to  which  the  pupil  is  refened 

925.  Have  the  cornea  and  the  humors  of  the  eye  different  degiees  of 
density  ?  What  is  said  of  the  crystalline  lens  ?  What  effect  has  the 
lifferent  density  of  the  parts  of  the  eye  upon  the  light  admitted  to  this 
organ  ?  926.  What  kind  of  lenses  do  the  humors  exhibit  ?  927-  What 
modifies  the  refracting  powers  of  transparent  mediums  ?  How  does  this 
principle  apply  to  the  humors  of  the  eye  ? 


408  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE 

circumstances  still  further  influence  the  refracting  charac- 
ter of  the  visual  organ.  The  achromatic  arrangement  of 
the  transparent  refracting  mediums  of  the  eye,  remedies 
the  aberration  of  refraction  in  the  different  portions  of  tho 
eye. 

928.  Again,  the  refracting  power  of  lenses  is  modified  by 
their  convexity  or  concavity.     The  more  convex  a  tens  is. 
the  shorter  the  distance  from  the  refracting  medium,  where 
the  different  refracted  rays  converge  to  a  focus.     To  adapt 
the   eye   to  view  objects   at   different   distances,   requires  a 
change   in  the  refracting  power  of  some  of  the  transparent 
mediums  of  the  eye. 

929.  Both  surfaces  of  the  crystalline  lens  are  oval,  not 
spherical,  and   the   refraction  of  the   rays  of  light  is  mainly 
effected  in  this  portion  of  the  eye.     Change  the  inclination 
of  this  lens,  so  that  different  portions  of  its  anterior  surface 
shall  be  directly  behind  the  pupil,  and  its  refracting  power  is 
increased  or  diminished,  as  the  surface  presented  is  more  or 
less  convex. 

930.  To  view  objects  at  a  distance,  a  less  convex  lens  is 
needed  than  in  examining  articles  very  near  the  eye ;  and 
this  organ,  from  its  structure,  has  the  power  of  adaptation  to 
different  distances.     It  is  supposed  that  the   muscular  sub- 
stance of  the  ciliary    body   and    processes  changes,    by  its 
contraction,  the  inclination  of  the  crystalline  lens.     Without 
this,   or   some   other   adapting    power,  a  picture  of   objects 
at  different  distances  would  not  be  formed  upon  the  retina, 
and  the  vision   of  every  person   would  be  defective,  except 
in    reference  to  objects   at   certain   definite    distances   from 
the  eye. 

928.  What  modifies  the  refracting  power  of  lenses  ?  What  is  necessary 
to  adapt  the  eye  to  view  objects  at  different  distances  ?  929.  Where  is  the 
refraction  of  the  rays  of  light  mainly  effected?  930.  When  we  view 
objects  at  a  distance,  what  kind  of  lens  is  required  ?  Has  the  eye  th**- 
o<»wer  of  adapting  itself  to  different  distances  ?  How  is  it  effected  ? 


PHYSIOLOGY    OF    THE    ORGANS    OF    VISION. 


40!> 


Observation.  It  is  well  known  that  a  separate  image  is 
formed  on  each  eye,  and,  if  they  are  not  in  the  same  direc- 
tion, the  objects  will  appear  double.  This  is  proved  by 
pressing  one  eye,  so  that  the  rays  of  light  cannot  enter  it  in 
the  same  direction  as  they  do  in  the  other ;  consequently,  the 
vision  is  double. 

931.  By  the  action  of  the  muscles  of  the  eye,  it  is  turned 
in  different  directions,  so  that  objects  can  be  examined  upon 
each  side,  as  well  as  in  front,  without  turning  the  body.  By 
the  slight  or  intense  action  of  the  straight  muscles,  the  eye  is 
more  or  less  compressed,  and  the  form  of  the  globe  is 
changed,  together  with  the  relative  positions  of  the  different 
humors.  This  modification  also  adapts  the  eye  to  view  ob- 
jects at  di  tie  rent  distances. 

Fig.  143. 


Fig.  143.     1,  A  pen,  an  inverted  image  of  which  is  (minted  on  the  retina  of  tlm 
yt-,  at  2.     The  image  of  all  objects  upon  the  expansion  of  the  optic  nerve,  is  inverted 
•>>•  the  crossing  of  the  rays  of  light  from  objects  as  they  traverse  the  pupil. 

Observation.  If  the  eye  is  fixed  for  a  time  on  some  object 
which  is  distinguished  with  difficulty,  there  is  a  painful  sensa- 
tion, similar  to  that  experienced  by  other  muscles  of  the  body 
when  used  too  long.  This  is  called  u  straining  the  eye." 

932.  When  the  refraction  of  the  rays  of  light  is  too  great, 
as  in  over-convexity  of  the  cornea,  or  the  crystalline  lens,  or 
the  vitreous  humor,  or  all  of  them,  the  image  is  formed  a 

'What  does  fig.  143  represent  ?  931.  "Why  can  we  see  objects  at  the  side 
MS  well  as  in  front  of  the  eye,  without  turning  the  body  ?  What  is  the 
;'•'=<_'.  when  the  eye  is  fixed  .->n  an  object  thai  is  iudistinctl)  seen? 


410  ANATOMY,    PHYSIOLOGY,    AND    TTYGYENE. 

little  in  front  of  the  retina.  Persons  thus  affected  cannot  see 
distinctly,  except  at  a  very  short  distance.  This  infirmity 
is  called  near,  or  short-sightedness.  This  defect  is  in  a  great 
measure  obviated  by  the  use  of  concave  glasses,  which  scatter 
the  luminous  rays,  and  thus  counterbalance  the  too  strong 
refracting  force  of  the  eye. 

933.  When  the  different  parts  of  the  eye  are  not  sufficient- 
ly convex,  the  image  is  formed  beyond  the  retina,  and  thus 
only  distant  objects  are  distinctly  seen.  This  defect  is  called 
long-sightedness.  The  feebleness  in  the  refracting  power  of 
the  eye  may  be  caused  by  disease  ;  but  usually  it  is  a  conse- 
quence of  old  age,  and  is  remedied  by  wearing  spectacles 
with  convex  glasses. 


HYGIENE   OF  THE  ORGANS  OF  VISION. 

934.  The  eye,  like  other  organs  of  the  lody,  should  be 
used,  and  then  rested.     If  we  look  intently  at  an  object  for 
a   long  time,  the  eye  becomes  wearied,  and  the   power  of 
vision  diminished.     The  .observance  of  this  rule  is  particular- 
ly needful  to  those  whose  eyes  are  weak,  and  predisposed  to 
inflammation.     On  the  contrary,  if  the  eye  is  not  called  into 
action,  its  functions  are  enfeebled. 

935.  Sudden  transitions  of  light  should  le  avoided.     The 
iris  enlarges  or  contracts,  as  the  light  that  falls  upon  the  eye 
is    faint   or   strong  ;    but   the   change    is   not   instantaneous. 

932.  "What  is  short-sightedness  ?  How  is  the  defect  remedied  ?  933.  What 
is  long-sightedness  ?  How  is  the  defect  remedied  ?  934 — 942.  Give  the 
iu/yiene  of  the  organs  of  vision.  934.  Do  the  same  principles  apply  to  the 
use  of  the  eye  as  to  other  organs  ?  What  is  the  effect  if  the  eye  is  fixed 
intently  on  an  object  for  a  long  time?  What  results  if  the  eye  is  not 
culled  into  action  ?  935.  Why  should  sudden  transitions  of  light  be 
avoided  ? 

Note.  Let.  the  anatomy  and  physiology  of  the  eye  be  reviewed  from 
(ills  U'i)  and  143.  or  from  anatomical  outline  plate  No.  10. 


HYGIENE    OF    THE    ORGANS    OF    VISION.  411 

Hence  the  imperfect  vision  in  passing  from  a  strong  to  a  dim 
light,  and  the  overwhelming  sensation  experienced  on  emerg- 
ing from  a  dimly-lighted  apartment  to  one  brilliantly  illu- 
minated. A  common  cause  of  am-aur-o'sis,  or  paralysis  of 
the  retina,  is,  using  the  eye  for  a  long  time  in  a  very  intense 
light. 

936.  Long- continued  oblique  positions  of  the  eye  should  be 
avoided-,  when  viewing  objects.     If  the  eye  is  turned  obliquely 
for  a  long  time  in  viewing  objects,  it  may  produce  an  unnat- 
ural contraction  of  the  muscle  called  into  action.     This  con- 
traction of  the  muscle  is  termed  stra-bis'mus,  or  cross-eye. 
The  practice  of  imitating  the  appearance  of   a  person  thus 
affected,  is  injudicious,  as  the  imitation,  designed  to  be  tem- 
porary, may  become  permanent. 

Observation.  The  vision  of  a  "  cross-eye "  is  always 
defective.  In  general,  only  one  eve  is  called  into  action,  in 
viewing  the  object  to  which  the  mind  is  directed.  This 
defect  can  be  remedied  by  a  surgical  operation,  which  also 
corrects  the  position  of  the  eye. 

937.  Children  should  be  trained  to  use  the  eye  upon  objects 
at  different  distances.     This  is  necessary,  in  order  that  the 
vision  may  be  correct  when  objects  at  various  distances  are 
viewed.     Any  action  unnatural  to  the  muscles,  if  frequently 
repeated,  may  and  will  modify  the  character  and  action  of 
the  parts  so  operated  upon.     If  a  limb,  as  the  arm,  be  kept 
flexed  for  a  long  time,  one  set  of  muscles  will  be  relaxed  and 
elongated,  and  another  will  be  shortened,  and  its  contractile 
power  will  be  increased.      The    same    principle    is   true  of 
the  eye. 

What  causes  palsy  of  the  retina  ?  936.  Why  should  we  avoid  oblique 
positions  of  the  eye  in  viewing  objects  ?  What  is  said  of  the  practice  of 
imitating  persons  thus  affected  ?  What  is  said  in  reference  to  the  vision 
of  a  "  cross-eye  "  ?  937.  Why  should  children  be  trained  to  use  the  eye 
upon  objects  at  different  distances  ?  What  is  the  effect  if  an  unnatural 
action  of  the  muscles  is  frequently  repeated  ?  Does  the  same  principle 
apply  to  the  eye  ? 


412  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

938.  In  viewing  objects  very  near  the    eye,  the  ciliary 
processes  are  called  into  action  to  produce  a  proper  inclina- 
tion of  the  crystalline  lens,  so  that  the  rays  of  light  may  be 
properly  refracted  to  form  a  perfect  image  on  the  retina.     In 
looking  at  objects  at  a  great  distance,  the  ciliary  processes 
are  called  into  a  different  action,  to  produce  a  different  in- 
clination of  the  lens.     Let  either  of  these  actions  be  repeated, 
ygain  and  again,  for  weeks  and  months,  and  they  will  become 
natural,  and  the  acquired  inclination  will  be  permanent. 

939.  From   the    preceding   principle,  a    person    becomes 
short  or  long  sighted,  as  the  objects  to  which  the  eye  is  usually 
directed  are  near  or  remote.    This  is  one  reason  why  scholars, 
waichmakers,  and  artisans,  who  bring  minute  objects  near  the 
eye  to  examine  them,  are  short-sighted,  and  why  hunters  and 
sailors,  who  are  habituated  to  view  objects  at  a  distance,  are 
long-sighted. 

Observation.  In  the  management  of  children,  whether  in 
.he  nursery  or  school-room,  it  is  very  important  that  their 
oooks,  or  articles  upon  which  they  may  labor,  should  be  held 
at  an  appropriate  distance  from  the  eye.  Were  this  attended 
to  by  the  parent  or  instructor,  we  should  not  see  so  many 
oersons  with  defective  vision. 

940.  Cleanliness,  as  well  as  the  health  of  the  eye,  requhe 
hat  it  be  bathed  every  morning  with  pure  water,  either  cold 

or  tepid,  accompanied  with  as  little  rubbing  or  friction  as 
possible.  In  all  instances,  the  secretion  from  the  lachrymal 
glands,  that  sometimes  collects  at  the  angle  of  the  eye,  should 
be  removed,  as  it  contains  saline  matter. 

941.  When  small  particles,  or  dust,  get  upon  the  eye,  they 
produce  much    inconvenience,  which  is  often  increased  by 

938.  What  is  the  effect  of  repeatedly  using  the  eye  in  one  direction  ? 
939.  Why  are  artisans  and  scholars  generally  short-sighted  ?  Why  are 
sailors  and  hunters  long-sighted  ?  How  can  defective  vision  in  a  great 
degree  be  prevented?  940.  What  reasons  are  there  for  bathing  the  eye  ? 
fc41  How  can  dust  and  other  small  particles  be  removed  from  the  eye? 


11VGIENE    OF   THE    ORGANS    OF    VISION. 

harsh  attempts  to  remove  them.  The  individual  should  bo 
placed  before  a  strong  light,  the  lids  held  open  with  one 
hand,  or  by  another  person,  and  the  particles  removed  with 
the  corner  of  a  fine  linen  or  silk  handkerchief. 

942.  Sometimes  the  substance  is  concealed  under  the 
upper  eyelid,  and  it  may  then  be  exposed  by  turning  baric 
the  lid  in  the  following  manner :  Take  a  knitting-needle,  or 
small,  slender  piece  of  stick,  which  is  perfectly  smooth,  and 
place  it  over  the  upper  lid,  in  contact  with,  and  just  under 
the  edge  of  the  orbit ;  then,  holding  it  firmly,  seize  the  eye- 
lashes with  the  fingers  of  the  disengaged  hand,  and  gently 
turn  the  lid  back  over  the  stick  or  needle.  The  inner  side 
of  the  lid  can  then  be  examined,  and  any  substance  removed 
that  may  have  been  there  concealed.  Too  many  trials  ought 
not  to  be  made,  if  unsuccessful,  as  much  inflammation  may 
be  induced ;  but  a  surgeon  should  be  consulted  as  soon  as 
possible. 

Observation.  Eyestones  ought  never  to  be  placed  in  the 
eye,  as  they  often  cause  more  pain  and  irritation  than  the  evil 
which  they  are  intended  to  remedy. 


942.    How  removed  from  the  upper  eyelid  ?     Why  should  aot  eyestoucs 
be  used? 

35* 


411  ANATOMY,    PHYSIOLOGY,    AND    HY6IKNE. 


CHAPTER     XL  VI. 

THE    SENSE    OF    HEARING. 

043.  THE  sense  of  hearing  is  next  in  importance  to  that 
of  vision.  Through  this  sense  we  are  enabled  to  perceive 
sounds,  that  not  only  subserve  to  our  comfort  and  pleasure, 
but  are  instrumental  in  promoting  our  intellectual  enjoyments. 
The  organ  of  hearing,  or  the  ear,  is  one  of  the  most  compli- 
cated in  the  human  body. 

ANATOMY  OF  THE  ORGANS  OF  HEARING. 

944.  The  EAR  is  composed  of  three  parts :   1st.  The  Ex 
lernal  Ear.     2d.  The  Tym'pan-um,  or  middle  ear.     3d.  The 
La'by-rinlh,  or  internal  ear. 

945.  The  EXTERNAL  EAR  is  composed  of  two  parts  :  The 
Pin'na,  (pavilion  of  the  ear,)  and  the  Me-a'tus  Aud-it-o'ri-us 
Ex-ter'nus,  (auditory  canal.) 

946.  The  PINNA  is  a  cartilaginous  plate  which  surrounds 
the  entrance  of  the  auditory  canal.     It  presents  many  ridges 
and   furrows,  arising   from   the    folds   of  the   cartilage    that 
form  it. 

Observation.  The  pinna,  in  many  animals,  is  movable ; 
in  those  that  pursue  their  prey,  it  is  generally  directed  for 
ward ;  in  timid  animals,  as  the  hare  and  rabbit,  it  is  directed 

943.  What  is  said  of  the  importance  of  hearing  ?  Is  the  ear  com  plicated 
in  its  structure  ?  944 — 962.  Give  the  anatomy  of  the  organs  of  hearhi;/. 
044.  Of  how  many  parts  is  the  ear  composed  ?  Name  them.  94o.  Give  the 
parts  of  the  external  ear.  946.  Describe  the  pinna.  What  is  said  in  refer- 
ence to  the  pinna  of  many  animals  ? 


ANATOMY    OF    THE    ORGANS    OF    HJiAKlMU.  11?. 

Backward.     In  man,  this  part  is  but  slightly  under  the  control 
of  the  will. 

947.  The  MEATUS  AUDITORIUS  is  a  canal  partly  cartilagi- 
nous, and  partly  bony,  about  an  inch  in  length,  which  extends 
inward  from  the  pinna  to  the  Mem'bra-na  Tym'pan-i,  (drum  of 
the  ear.)  It  is  narrower  in  the  middle  than  at  the  extremities. 
It  is  lined  by  an  extremely  thin  pouch  of  cuticle,  which,  when 
withdrawn,  after  maceration,  preserves  the  form  of  the  canal. 
Some  stiff,  short  hairs  are  also  found  in  the  interior  of  the 
channel,  which  stretch  across  the  tube,  and  prevent  the  ingress 
of  insects.  Beneath  the  cuticle  are  a  number  of  small  folli 
des,  which  secrete  the  wax  of  the  ear. 


Fig.  144.  A  representation  of  the  four  bones  of  the  ear.  The  smallest  is  highly 
magnified.  This  bone  is  early  matured,  and  in  the  adult  it  becomes  united  with  th<3 
incus.  These  bones  are  retained  iu  their  places  and  moved  by  three  ligaments  and  four 
muscles. 

948.  The  MEMBRANA  TYMPANI  is  a  thin,  semi-transparent 
membrane,  of  an  oval  shape.     It  is  about  three  eighths  of  an 
inch  in  diameter,  and  is  inserted  into  a  groove  around  the 
circumference    of  the    meatus,   near   its   termination.     This 
membrane  is  placed   obliquely  across   the  area  of  that  tube. 
It   is  concave   toward   the    meatus,  and   convex  toward  the 
tympanum. 

949.  The  TYMPANUM  consists  of  an  irregular  bony  cavity, 
situated  within  the  temporal  bone.     It  is  bounded  externally 
by  the  membrana  tympani  ;  internally  by  its  inner  wall  ;  and 
in  its  circumference  by  the  petrous  portion  of  the  temporal 

947.  What  is  the  meatus  auditorius  ?  What  is  found  in  this  canal  ?  What 
is  their  use  ?  Where  is  the  wax  of  the  ear  secreted.  918.  Describe  the 
membrana  tympani.  919.  Where  is  the  tympanum  situated  ? 


lib 


ANATOMY,    I'll  YSJOLOGY,    AND    HYG1KNK. 


bone  and  mastoid  cells.  The  tympanum  contains  four  small 
bones,  called  the  os-sic'u-la  au-di'tus.  These  are  named  sepa- 
rately, the  mal'le-us,  in'cus,  sta'pes,  and  or-bic'u-lar. 

950.  There  are  ten  openings  in  the  middle  ear ;  five  large 
and  five  small.  The  larger  openings  are,  the  Me-a'tus  And 
it-o'ri-us  Ex-ter'nus,  Fe-nes'tra  O-va'tis,  (oval  window,)  Fe- 
nes' tr a  Ro-tun'da,  (round  window,)  Mas'toid  Cells^  and 
Eu-sta'chi-an  Tube. 

Fig.  145. 


Fig.  145.  A  representation  of  the  pinna,  mcatus,  membrana  tympani,  bones  of  fbe 
ear,  and  semicircular  canals,  a,  The  pinna,  c,  The  meatus  auditorius  cxternus. 
g,  The  membrana  tympani.  k,  The  tympanum,  e,  The  bor.es  of  the  ear.  A,  Tim 
semicircular  canals.  /,  The  cochlea.  A,  The  vestibule,  i,  The  Eustachian  tn»>e 
d,  The  auditory  nerve. 

951.  The  FENESTRA  OVALIS  is  the  opening  of  communica- 
tion between  the  tympanum  and  the  vestibule.     It  is  closed 
by  the  foot  of  the  stapes,  or  bone  of  the  ear,  and  by  the  lining 
membrane  of  both  cavities. 

952.  The.  FENESTRA  ROTUNDA  serves  to  establish  a  covn- 

What  does  this  cavity  contain?  950.  How  many  openings  in  the  tym- 
panum ?  Explain  fig.  145.  951.  Describe  the  fenestra  ovalis.  95'J.  TU 
fenestra  rotunda. 


ANATOMY    OF    THE    ORGANS    OF    HEARING.  417 

m'unication  between  the  tympanum  and  the  cochlea.  It  ia 
closed  by  a  proper  membrane,  as  well  as  by  the  lining  of  both 
cavities. 

953.  The  MASTOID  CELLS  are  very  numerous,  and  occupy 
the  whole  of  the  interior  of  the  mastoid  process  of  the  tem- 
poral bone,  and  part  of  the  petrous  bone.  They  communicate, 
by  a  large,  irregular  opening,  with  the  upper  and  posterioi 
circumference  of  the  tympanum. 

Fig.  146. 


Fig.  146.  A  view  of  the  labyrinth  laid  open.  This  figure  is  highly  magnified. 
,  1,  The  cochlea.  2,  H,  Two  channels,  that  wind  two  s..i .  ••  half  turns  an. HI;.!  a 
central  point,  (5.)  7,  The  central  portion  of  the  labyrinth,  (vr.-tihule.)  8,  Th-  f,  n- 
men  rotundurn.  9,  The  fenestra  ovalis.  11,  12,  !?,  14,  15,  16,  17,  18,  The  seniiciini- 
lar  canals.  The  cochlea  and  semicircular  canals  open  into  the  vestibule. 

954.  The  EUSTACHIAN  TUBE  is  a  canal  of  communication, 
extending  obliquely  between  the  pharynx  and  the  anterior 
circumference  of  the  tympanum.  In  structure  it  is  partly 

953.  Where  are  the  mastoid  cells  ?  Explain  fig.  146.  954.  Describe  the 
Eustuchian  tuoe. 


418  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

fibro-cartilaginous  and  partly  bony.  It  is  broad  and  expanded 
at  its  pharyngeal  extremity,  and  narrow  and  compressed  at 
the  tympanum. 

955.  The   small  openings  of  the  middle  ear  are  for  the 
entrance  and  exit  of  the  chorda  tympani,  (a  small  nerve  that 
crosses  the   tympanum,)  and    for  the   exit  of  the    muscles 
that  act  upon  the  membrana  tympani  and  bones  of  the  ear. 

956.  Tho  LABYRINTH  consists  of  a  membranous  and  a  bony 
portion.     The  bony  labyrinth   presents  a  series  of  cavities 
which  are  channelled  through  the  substance  of  the   petrous 
bone.     It  is  situated  between  the  cavity  of  the  tympanum  and 
the   Aud'it-o-ry  Nerve.     The   labyrinth    is    divided  into  the 
Ves'ti-bule,  Sem-i-cir'cu-lar  Canals,  and  Coch'le-a. 

957.  The    VESTIBULE    is   a   small,   three-cornered   cavity, 
situated  immediately  within  the  inner  wall  of  the  tympanum. 

958.  The   SEMICIRCULAR  CANALS  are  three  bony  passages 
which  communicate  with  the  vestibule,  into  which  two  of  them 
open  at  both  extremities,  and  the  third  at  one  extremity. 

959.  The  COCHLEA  forms  the  anterior  portion  of  the  laby- 
rinth.    It  consists  of  a  bony  and   gradually  tapering  canal, 
about  one  and  a  half  inches  in  length,  which  makes  two  turns 
and  a  half,  spirally,  around  a  central  axis,  called  the  mo-di'o-lus. 
The  modiolus  is  large   near  its  base,  where   it  corresponds 
with  the  first  turn  of  the  cochlea,  and  diminishes  in  diameter 
toward  its  extremity. 

960.  The  interior  of  the  canal  of  the  cochlea  is  partially 
divided  into  two  passages,  by  means  of  a  bony  and  membra- 
nous plate.     At  the  extremity  of  the  modiolus,  the  two  pas- 
sages communicate  with  each  other.     At  the  other  extremity, 
one  opens  into  the  vestibule ;  the  other  into  the  tympanum,  by 

955.  What  passes  through  the  small  openings  of  the  middle  ear } 
956.  Of  what  does  the  labyrinth  consist  ?  Give  the  parts  of  the  internal 
ear.  957.  Describe  the  vestibule.  958.  What  is  said  of  the  semicircular 
canals  ?  959.  Why  is  the  cochlea  so  called  ?  Of  what  does  it  consist  ? 
960.  How  is  the  interior  of  the  canal  of  the  cochlea  divided?  Wheie  do 
they  communicate  with  each  other  ? 


ANATOMY  OF  THE  ORGANS  OF  HEARING.       41U 

ihe   foramen  rotunclum.     The   internal   surface   of  the   bony 
labyrinth  is  lined  by  a  fibro-serous  membrane. 

961.  The  membranous  labyrinth  is  smaller  in  size,  but  a 
perfect  counterpart,  with  respect  to  form,  of  the  bony  vestibule, 
cochlea,  and  semicircular  canals.  Within  this  labyrinth  are 
two  small,  elongated  sacs,  which  are  filled  with  a  fluid. 

Fig.  147. 


Fig.  147.  A  view  of  the  auditory  nerve.  1,  The  spinal  cord.  2,  The  medulla 
tblongiita.  3,  The  lower  part  of  the  brain.  4,  The  auditory  nerve.  5,  A  branch  to 
the  semicircular  canals.  6,  A  branch  to  the  cochlea. 

962.  The  AUDITORY  NERVE  enters  the  temporal  bone  upon 
its  internal  surface,  and  divides  into  two  branches,  at  the  bot- 
tom of  the  cavity  of  the  internal  ear.  These  branches  enter 
flie  structure  of  the  elongated  sacs  and  membranous  labyrinth, 
radiating  in  all  directions,  and  finally,  they  terminate  upon 
the  inner  surface  of  the  membrane,  in  minute  papillae,  resem- 
bling those  of  the  retina. 

By  what  is  the  internal  labyrinth  lined  ?  961.  Describe  the  membranous 
labyrinth.  What  does  fig.  147  represent  ?  962.  Where  does  the  auditory 
nerve  enter  and  divide  ?  Where  do  the  branches  of  the  auditory  nerve 
enter  and  terminate  ? 


4^  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

CHAPTER     XLVII. 

PHYSIOLOGY  OF  THE  ORGANS  OF  HEARING. 

963.  HEARING  is  that  function  by  which  we  obtain  a  knowl- 
edge of  the  vibratory  motions  of  bodies,  which  constitute  sounds. 
The  precise  function  of  all  the  different  parts  of  the  ear  is  not 
known. 

964.  The  function  of  that  part  of  the  external  ear  which 
projects  from  the  head  is  to  collect  sounds  and  reflect  them 
into  the  meatus. 

965.  The  membrana  tympani  serves  to  facilitate  the  trans- 
mission of  sounds,  and  also  to  moderate  their  intensity.     It  is 
so  arranged  that  it  can  be  relaxed  or  tightened. 

Observation.  This  membrane,  when  healthy,  has  no  open- 
ing ;  and  it  must  be  apparent  that  the  apprehension  which  is 
often  expressed,  that  insects  will  penetrate  further,  is  grounvl- 
less.  The  pain  is  owing  to  the  extreme  sensibility  of  the 
membrana  tympani. 

966.  The  supposed  office  of  the  tympanum  is  to  transmit 
the  vibrations  made  on  the  membrana  tympani  to  the  internal 
ear.     This  is  effected  by  the  air  which  it  contains,  and  by  the 
chain  of  small  bones  that  are  enclosed  in  this  cavity. 

967.  The  use  of  the  Eustachian  tube  is  to  admit  air  into 
the  ^tympanum,  which  renders  the  pressure  on  both  sides  equal, 
and  thus  its  membrane  is  kept  in  a  proper  state  of  tension. 

963 — 971.  Give  the  physiology  of  the  organs  of  hearing.  963.  What  is 
hearing  ?  Are  the  precise  functions  of  the  different  parts  of  the  ear  known  ? 
964.  What  is  the  function  of  the  external  ear  ?  965.  Of  the  membrana 
tympani  ?  What  observation  in  reference  to  this  membrane  ?  966.  What  in 
the  supposed  office  of  the  middle  ear  ?  967.  What  is  the  use  of  the  Eu 
stachian  tube  ? 


PHYSIOLOGY    OF    THE    ORGANS    OF    HEARING.  4v.l 

Observation.  When  near  a  cannon,  or  a  field-piece,  about 
being  discharged,  by  opening  the  mouth  the  impression  upon 
the  auditory  nerve  will  be  diminished,  and  the  unpleasant  sen- 
sation lessened.  This  is  the  result  of  the  air  in  the  middle  eai 
escaping  through  the  Eustuchian  tube,  when  the  vibrations  of 
the  membrana  tympani  are  violent. 

Fig.  148. 


P  g.  148.  A  view  of  all  the  parts  of  the  ear.  1,  The  tube  that  leads  to  the  internal 
ear.  2,  The  membrana  tympani.  3,  4,5,  The  bones  of  the  ear.  7,  The  central  part 
of  the  labyrinth,  (vestibule.)  8,  9,  10,  The  semicircular  canals.  11,  12,  The  chan- 
nels of  the  cochlea.  13,  The  auditory  nerve.  14,  The  channel  from  the  middle  eai 
to  the  throat,  (Eustachian  tube.) 

968.  But  little  is  known  of  the  functions  of  the  internal 
ear ;  its  parts  are  filled  with  a  watery  fluid,  in  which  the  fila- 
ments of  the  auditory  nerve  terminate. 


What  observation  in  this  connection  ?    968.  What  is  the  function  of  the 
internal  ear  ? 


422  ANATOMY,    PHYSIOLOGY,   ANU    HYGIENE 

969.  Many  of  the  parts  just  enumerated  aid  in  hearing,  bul 
are  not  absolutely  essential  to  this  sense      But  if  the  vestibule 
and  auditory  nerve  are  diseased  or  destroyed,  no  sound  is  then 
perceived.     If  this  sense  is  destroyed  in  early  life,  the  peison 
also  loses  the   power  of  articulating  words.     Hence  a  man 
born  deaf  is  always  dumb. 

970.  The  transmission  of  sound  through  the  different  parts 
of  the  ear  will   now   be  explained  by  aid  of  fig.  148.     The 
vibrations  of  air  are  collected  by  the  external  ear,  and  con- 
ducted through  the  tube  (1)  to  the  membrana  tympani,  (2.) 
From  the  membrane  vibrations  pass  along  the  chain  of  bones, 
(3,  4,  5.)     The  bone  5  communicates  with  the  internal  ear, 
(7,  8,  9,  10,  11,  11,  11,  12,  12,  12.)     From  the  internal  ear 
the  impression  is  transmitted  to  the  brain  by  the  nerve,  (13.) 

971.  The  auditory  nerve,  like  the  optic,  has  but  one  func- 
tion, that  of  special  sensibility.     The   nerves  which  furnish 
the  ear  with  ordinary  sensibility,  proceed  from  the  fifth  pair. 

HYGIENE  OF  THE  ORGANS  OF  HEARING. 

972.  Hearing,  like  the  other  senses,    is  capable  of  very 
great  improvement.     By  cultivation,  the  blind  are  enabled  to 
judge  with  great  accuracy  the  distance  of  bodies  in  motion, 
and  even  the  height  of  buildings.     It  is  also  capable  of  im- 
provement when  all  the  other  senses  are  perfect.     Thus  the 
Indian  will  distinguish  sounds  that  are  inaudible  to  the  white 
man. 

969.  What  parts  of  the  ear  are  essential  in  order  to  hear  sounds  ? 
What  follows  loss  of  hearing?  971.  What  is  the  office  of  the  auditory 
nerve  ?  What  nerves  convey  ordinary  sensibility  to  the  ear  ?  972 — 
978.  G-ive  the  hygiene  of  the  organs  of  hearing.  972.  Is  this  sense  capable 
of  improvement  ?  How  does  this  sense  aid  the  blind  ?  Is  it  also  capable 
of  improvement  when  all  the  other  senses  are  perfect  ?  In  whom  is  this 
illustrated  ? 

Note.  Let  the  anatomy  and  physiology  of  the  organs  of  hearing  be 
reviewed,  from  fig.  148,  or  from  anatomical  outline  plate  No.  10 


HYGIENE    OF    THE    ORGANS    OF    HEARING.  4^ 

973.  Acute  hearing  requires  perfection  in  the  structure  and 
functions  of  the  different  parts  of  the  ear,  and  that  portion  of 
the  brain  from  which  the  auditory  nerve  proceeds.     Deafness 
is  by  no  means  unfrequent.     We  will  now  advert  to  some  of 
the  common  causes  of  imperfect  hearing. 

974.  The  structure   or  functional  action  of  the  brain  may 
be  deranged  by  inflammation,  by  compression,  or  by  debility, 
and  produce  deafness.     The  first  is  seen  during  inflammatory 
affections  of  the  brain,  and  in  fevers ;  the  second  is  seen  in 
accidental  injuries  of  the  head  ;  the  third  is  seen  in  old  age, 
and  after  severe  diseases  of  the  head,  and   fevers.     In  these 
cases,  applications  to,  and  operations  upon,  the  ear  do  no  good. 
The  only  remedy  is  to  remove,  if  possible,  the  diseased  con- 
dition of  the  brain. 

975.  Imperfect  hearing  may  be  produced  by  the  destruction 
of  the  membrana  tympani,   or  removal  of  the  bones  of  tht, 
ear,  or  the   parts  within  the  labyrinth.     In  these  instances, 
medical  treatment  is  of  no  avail,  as  the  destroyed  parts  can- 
not be  restored. 

976.  Hearing  may  be  rendered  defective  by  a  diminution  of 
the  vibratory  character  of  the  membrana  tympani.     This  may 
result  from  a  thickening  of  this  membrane,  or  from   an  ac- 
cumulation of  wax  upon  its  outer  surface.      The  increased 
thickness  is  usually  the  result  of  inflammation,  either  acuie 
or  chronic.     The  proper  treatment  is  such  as  is  efficient  to 
remove  inflammatory  action. 

Observations.  1st.  The  introduction  of  heads  of  pins  into 
the  ear  is  a  frequent  cause  of  chronic  inflammation  of  the 
membrana  tympani.  Hence  this  practice  should  never  bo 
adopted,  and  if  acquired,  should  be  abandoned. 

973.  On  what  does  acute  hearing  depend?  974.  State  effects  on  the 
hearing  in  some  conditions  of  the  brain.  How  relieved?  975.  Of  the 
effect  on  hearing  when  the  bones  of  the  ear  or  the  labyrinth  are  destroyed  ? 
Is  medical  treatment  of  any  avail  ?  976.  What  conditions  of  the  drum  of 
r.ho  ear  may  impair  hearing  ?  How  relieved?  What  is  said  of  the  iatro 
dilution  of  pins  to  cleanse  the  ear  ? 


424  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

2d.  The  accumulations  of  viscid  wax  may  be  softened  by 
dropping  some  animal  oil  into  the  ear,  and  then  removing  it  by 
ejecting  warm  soap  suds  a  few  hours  subsequent  to  the  use  of 
the  oil.  This  may  be  repeated  for  several  successive  days. 

977.  Hearing  may  be  impaired  by  obstruction  of  the  Eu- 
stachian  tube.     The  closure  of  this  canal  diminishes  the  vibra- 
tory character  of  the  air  within  the  tympanum,  in  the  same 
manner  as  closing  the  opening  in  the  side  of  a  drum.     For 
the  same  reason,  enlarged  tonsils,  inflammation  and  ulceration 
of  the  fauces  and  nasal  passages  during  and  subsequent  to  an 
attack  of  scarlet  fever,  and  the   inflammation  attending  the 
u  sore  throat "  in  colds,  are  common  causes  of  this  obstruc- 
tion. 

978.  The  treatment  of  such  cases  of  defective  hearing,  is 
to  have  the  tonsils,  if  enlarged,  removed  by  a  surgeon ;  for 
the  inflammation  and  thickening  of  the  parts  remedial  means 
should  be  applied,  directed  by  a  skilful  physician.     The  nos- 
trums for  the  cure  of  deafness  are  generally  of  an  oleaginous 
character,  and  may  be  beneficial  in  cases  of  defective  hearing 
caused  by  an  accumulation  of  wax  upon  the  drum  of  the  ear, 
but  in  this  respect  they  are  no  better  than  the  ordinary  animal 
oils. 

What  is  the  remedy  where  there  is  an  accumulation  of  wax  ?  977.  What 
is  the  effect  on  hearing  if  the  Eustachian  tube  is  obstructed  ?  978.  What 
is  the  treatment  when  deafness  is  caused  by  inflammation  or  ulceration  ?* 
the  fauces  ?  What  is  said  of  the  nostrums  used  for  deafness  ? 


MEANS    OF    PRESERVING    THE    HEALTH. 


CHAPTER    XLVIII 

MEANS    OF    PRESERVING    THE    HEALTH.* 

979.  OUR  bodies  are  constituted  in  harmony  with  certain 
laws,  and  every  person  should  learn  these,  in  order  to  regu- 
late his  actions  and  the  performance  of  his  duties,  so  that 
health    may   be   unimpaired,  and  the  power   of   enjoyment, 
activity,  and  usefulness  continue  while  life  lasts. 

980.  It  is  a  law  of  the  bones  and  the   muscles,  that  they 
should   either  be  used  in  some  vocation,  or  called  into  action 
by  some  social  play  and  active  sport. 

981.  All  admit  that  food  is  necessary  to  sustain  life ;  and 
unless  it  be  of  a  proper  quality,  taken  in  proper  quantities,  and 
at  proper  times,  the  functions  of  the  digestive  organs  will  be 
deranged,  and  disease  produced. 

982.  Pure  air  is  essential  to  the  full  enjoyment  of  health. 
The  impure  air  of  unventilated  rooms  may  be  breathed,  and 
the  effect  be  so  gradual  as  not  to  arrest  attention ;  yet  it  ra 
a  violation  of  the  physical  laws,  and,  sooner  or  later,  we  pu^ 
the  penalty  in  disease  and  suffering. 

983.  The  body  also  requires  sleep ;  and  if  it  is  not  taker 
at  the  right  time,  or  with  regularity,  we  do  not  feel  full  refresh- 


*  It  is  advised,  that  a  thorough  review  of  the  hygiene  of  the  pre- 
ceding chapters  be  given  from  the  suggestions  contained  in  this. 

979.  Why  is  it  incumbent  on  every  person  to  learn  the  laws  of  health  ? 
980.  Give  a  law  of  the  muscles.  981.  In  preserving  the  health,  is  it  neces- 
sary to  give  attention  to  the  food  which  is  eaten  ?  Why  ?  982.  What 
beside  food  is  essential  to  the  full  enjoyment  of  health  ?  What  is  said  of 
the  impure  air  of  unventilated  rooms  ?  983.  What  should  be  observed  ir 
regard  to  sleep  ? 


2  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

merit  frum  "  tired  nature's  sweet  restorer."  Let  youth  be 
taught  that  "  early  to  bed  and  early  to  rise  "  gives  him  health 
a,nd  its  attendant  blessings.  The  brain,  like  other  organs  of 
the  body,  should  be  called  into  action  at  proper  times. 

984.  From  the  extent  of  the  surface  of  the  skin,  and  the 
close  sympathy  that  exists  between  it  and  those  organs  whose 
office  is,  to  remove  the  waste   particles  of  matter  from   the 
body,  it  therefore  becomes  very  important  in  the  preservation 
of  the  health,  that  the  functions  of  this  membrane  be  properly 
maintained. 

985.  The  function  of  the  circulatory  and  secretory  organs, 
together  with  the  operations  of  absorption  and  nutrition-,  should 
be  steadily  maintained,  as  vitality  and  the  generation  of  ani- 
mal heat  are  intimately  connected  with  these  processes,     hi 
the  proper  performance  of  these  functions,  very  much  depends 
on  the  observance  of  the  laws  of   the  muscular,  digestive 
respiratory,  dermoid,  and  nervous  apparatuses. 

REMOVAL  OF  DISEASE. 

986.  It  is  seldom   mat  a  physician  is  called  in  the  first 
stages  of  disease.     At  this  important  period,  the  treatment 
adopted  should  be  proper  and  judicious,  or  the  sufferings  of 
the  patient  are  increased,  and  life,  to  a  greater  or  less  degree, 
is  jeopardized.     Hence  the  utility  of  knowing  what  should  be 
done,  and  what  should  not  be  done,  in  order  that  the  health 
may  be  rapidly  regained. 

987.  In  all   instances  of  acute  disease,  it  is  proper  to  rest, 
not  only  the   body,  but  the  mind.     To  effect  this,  the  patient 
should  cease   from  phy  jical  exertion,  and  also  withdraw  his 

984.  Why  should  the  functions  of  the  skin  be  properly  maintained  r 
98-5.  Show  the  necessity  of  maintaining  properly  other  functions  of  the 
system.  986.  What  is  important  in  therirst  stages  of  disease  ?  987.  What 
u>  proper  in  all  instances  of  acute  disease  ?  How  can  it  be  effected  ? 


REMOVAL    OF    DISEASE. 


thoughts  from  study  and  business  operations.     This  should  be 
done,  even  if  the  person  is  but  slightly  indisposed. 

988.  Select  a  room  for  a  sick  person  that  is  exposed  to  as 
little  external  noise  as  possible,  as  impressions  made  on  the 
organ  of  hearing  greatly  influence  the  nervous  system.     Like- 
wise select  a  spacious,  well-ventilated  apartment,  that  has  no 
superfluous  furniture.     The  practice  of  placing  a  SICK  person 
.ri  a  small,  ill-arranged  sleeping-room,  when  a  more  spacious 
room  can  be  used,  is  poor  economy,  not  to  say  unkind. 

989.  Care  is  necessary  in  regulating  the  light  of  a  sick- 
room.    While    a   strong   light  would  produce   an   increased 
action  of  the  vessels  of  the  brain,  a  moderate  light  would  be 
an  appropriate  stimulus  to  this  organ.     It  is  seldom  or  never 
necessary  to  exclude  all  light  from  the  sick-chamber. 

990.  A  sick  person,  whether  a  child  or  an  adult,  should  not 
be  disturbed  by  visitors,  even  if  their  calls  are  short.     The 
excitement  of  meeting  them  is  followed  by  a  depression  of  the 
nervous  system.     The  more  dangerous  and  apparently  nearer 
death    the   sick  person  is,  the   more   rigorous  should  be  the 
observance  of  this  suggestion.     Nor  should  the  sick-room  be 
opened  to  privileged  classes  ;  for  the  excitement  caused  by  a 
visit  from  relations  and  the  virtuous,  will  do  as  much  injury  to 
the  sick,  as  that  produced  by  strangers  and  the  vicious. 

991.  The  custom  of  visiting  and  conversing  with  sick  friends 
during  the  intervals  of  daily  labor,  and  particularly  on  Sunday, 
is  a  great  evil.     No  person  will  thus  intrude  herself  in  the  sick- 
chamber  who  cares  more  for  the  welfare  of  the  suffering  friend 
than  for  the  gratification  of  a  sympathetic  curiosity.     Inquiries 
can  be  made  of  the  family  respecting  the  sick,  and  compli- 
mentary or  necessary  messages  can  be  communicated  through 
the  nurse. 


988.  What  rooms  should  be  selected  for  the  sick  ?  Why  ?  989.  What 
is  said  in  reference  to  the  quantity  of  light  admitted  into  a  sick-room  ? 
&»d.  What  effect  have  calls  on  the  sick  ?  991.  What  is  said  of  the  custom 
of  calling  and  conversing  with  the  sick  during  the  intervals  of  daily  laboi  ? 


128  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

Illustration,  While  attending  a  Miss  B.,  of  N.  H.,  sick  of 
fever,  I  pronounced  her  better,  withdrew  medicine,  directed  a 
simple,  low  diet,  and  the  exclusion  of  all  visitors.  In  the 
evening  I  was  sent  for  to  attend  her.  There  was  a  violent 
relapse  into  the  disease,  which  continued  to  increase  in  sever- 
ity until  the  fourth  day,  when  death  terminated  her  sufferings. 
I  learned  that,  soon  after  I  gave  directions  that  no  visitors 
be  admitted  into  her  room,  several  particular  friends  were  per- 
mitted to  enter  the  chamber  and  talk  with  the  sick  girl.  Their 
conversation  produced  a  severe  headache  ;  and,  to  use  the 
language  of  the  patient,  "  it  seemed  as  if  their  talk  would 
kill  me  ; "  and  it  did  kill  her. 

992.  No  solid  food  should  be  taken  in  the  first  stages  of 
disease,  even  if  the  affection  is   slight.     The  thirst  can  be 
allayed  by  drinking  cold  water,  barley-water,  and  other  prep- 
arations of  an  unstimulating  character.     It  is  wrong  to  tempt 
the  appetite  of  a  person  who  is  indisposed.     The  cessation 
of  a  desire  for  food,  is  the  warning  of  nature,  that  the  system 
is  in  such  a  state  that  it  cannot  be  digested. 

993.  When  a  patient  is  recovering  from  illness,  the  food 
should  be  simple,  and  in  quantities  not  so  great  as  to  oppress 
the  stomach.     It  should  also  be  given  with  regularity.     "  E;it 
little  and  often,"  with  no  regard  to  regularity,  is  a  pernicious 
practice. 

994.  When  a  physician  attends  a  sick  person,  he  shoulJ 
have  the  special  management  of  the  food,  particularly  after 
the  medicine  has  been  withdrawn  and  the  patient  is  convales- 
cent.    The  prevailing  idea  that  every  person  may  safely  advise 
relative  to  food,  or  that  the  appetite  of  the  convalescing  per- 


Give  an  illustration.  992.  What  suggestion  relative  to  food  in  the  first 
stages  of  disease  ?  How  can  the  thirst  be  allayed  ?  993.  When  the 
patient  is  convalescent,  how  should  the  food  be  given  ?  What  is  said  of 
the  practice  of  eating  "little  and  often"?  994.  Who  should  have  thfi 
special  management  of  food  when  medicine  is  withdrawn?  What  idea 
prevails  in  the  community  ? 


REMOVAL    OF    DISEASE.  429 

«»on   is  a   competent  guide,   is  dangerous,  and  cannot  be  too 
much  censured. 

Illustration.  In  1832,  I  attended  a  Miss  M.,  sick  of  fever. 
After  an  illness  of  a  few  days,  the  fever  abated,  and  I  direct- 
ed a  simple,  unstimulating  diet.  Business  called  me  from 
.he  town  two  days.  During  my  absence,  a  sympathizing, 
officious  matron  called  ;  found  her  weak,  but  improving  ;  ana 
fold  her  she  needed  food  to  strengthen  her  ;  and  that  "  it 
would  now  do  her  good."  Accordingly,  eggs  and  a  piece  of 
beefsteak  were  prepared,  and  given  to  the  convalescent  girl. 
She  ate  heartily,  and  the  result  was  a  relapse  into  a  fever 
more  violent  than  the  first  attack. 

995.  It  is  very  important   in  disease  that  the  skin  be  kept 
clean.     A  free  action  of  the  vessels  of  this  part  of  the  body 
exerts  a  great  influence  in  removing  disease  from  the  internal 
organs,  as  well  as  keeping  them  in  health.     If  the  twenty  or 
thirty  ounces  of  waste,  hurtful  matter,  that  passes  through  the 
u  pores  "  of  the  skin  in  twenty-four  hours,  are  not  removed  by 
frequent  bathing  and  dry  rubbing,  it  deranges  the  action  of 
the  vessels  that  separate  this  waste  matter  from  the  blood,  and 
thus  increases  the  disease  of  the  internal  organs. 

Illustration.  Mrs.  M.  R.,  of  N.,  Mass.,  was  afflicted  with 
disease  of  the  lungs  and  Cough.  This  was  accompanied  with 
a  dry,  inactive  condition  of  the  skin.  As  medicine  had  no 
salutary  effect  in  relieving  her  cough,  she  was  induced  by  the 
advice  of  the  clergyman  of  the  parish  to  enter  upon  a  system- 
atic course  of  bathing  twice  every  day.  Soon  the  skin  became 
soft,  its  proper  functions  were  restored,  the  disease  of  the 
lungs  yielded,  and  the  cough  disappeared. 

996.  Every  sick   person  should   breathe  pure  air.     The 
purer  the  blood  that  courses  through  the  body,  the  greater  the 

Give  an  illustration  of  the  evil  effects  attending  such  an  idea.  995.  Does 
the  skin  exert  a  great  influence  in  removing  disease  from  the  internal 
jrir.'ins,  as  well  as  in  keeping  them  in  health  ?  Give  an  illustration 
996.  Why  should  every  sick  person,  particularly,  breathe  pure  \ir? 


ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

energy  of  the  system  to  remove  disease.  The  confined 
vitiated  air  of  the  sick-chamber,  not  unfrequently  prolongs  dis 
CLUSC  ;  and  in  many  instances,  the  affection  is  not  only  aggra 
»;ated,  but  even  rendered  fatal,  by  its  injurious  influences. 

Illustrations.  1st.  In  1833,  I  was  called,  in  consultation 
with  another  physician,  to  Mr.  H.,  who  was  much  debilitated, 
and  delirious.  For  several  successive  days  he  had  not  slept. 
His  room  was  kept  very  warm  and  close,  for  fear  he  would 
"  take  cold."  The  only  change  that  I  made  in  the  treatment, 
v»  as  to  open  the  door  and  window,  at  a  distance  from  the  bed. 
In  a  short  time,  the  delirium  ceased,  and  he  fell  into  a  quiet 
slumber.  From  this  time  he  rapidly  recovered,  and  the  de- 
lirium was  probably  the  result  of  breathing  impure  air. 

2d.  Formerly,  every  precaution  was  used  to  prevent  per- 
sons sick  of  the  small-pox  from  breathing  fresh  air.  When 
Mrs.  Ramsay  had  this  disease  in  Charleston,  S.  C.,her  friends, 
supposing  that  life  was  extinct,  caused  her  body  to  be  removed 
from  the  house  to  an  open  shed.  The  pure  air  revived  the 
vital  spark.  The  result  probably  would  have  been  different,  had 
she  been  kept  a  few  hours  longer  in  the  vitiated  air. 

997.  The   influence  of  habit  should  not  be  disregarded  in 
the  removal  of  disease.     If  food  or  drink  is  to  be  administered, 
however  small  in  quantity  or  simple  its  quality,  it  should  be 
given  at  or  about  the  time  when   the  ordinary  meals  were 
taken  in  health. 

998.  Again,  the  usual  time  when  the  patient  was  in  the 
habit  of  retiring  for  sleep  should   be  observed,  and  all  prepa- 
ration necessary  for  the  sick-room  during  the  night  should  be 
made  previous  to  this  hour.     Efforts  should  also  be  made  to 
evacuate  the  waste  matter  of  the  digestive  and  urinary  organs 
at  the  period  which  habit  has  formed  in  health.     This  is  not 

Are  not  diseases  prolonged,  and  even  rendered  fatal,  from  breathing  the 
im;  ure,  vitiated  air  of  the  sick-chamber?  Give  illustration  1st.  Give 
ilh:.  trut.ion  2d.  997.  What  is  said  respecting  the  influence  of  habit  in 
rci:  oving  disease  : 


FEMOVAL    OF    DISEASE.  451 

only  a   remedial  agent  in  disease,  but  often   precludes   the 
necessity  of  laxative  or  drastic  cathartics. 

1)99.  MEDICINE  is  sometimes  necessary  to  assist  the  natu< 
ral  powers  of  the  system  to  remove  disease;  but  it  is  only 
un  assistant.  While  emetics  are  occasionally  useful  in  remov- 
ing food  and  other  articles  from  the  stomach  that  would  cause 
disease  if  suffered  to  remain,  and  cathartics  are  valuable,  in 
some  instances,  to  relieve  the  alimentary  canal  of  irritating 
residuum,  yet  the  frequent  administration  of  either  will  cause 
serious  disease. 

1000.  Although  medicine  is  useful  in  some  instances,  yet, 
in  a  great  proportion  of  the  cases  of  disease,  including  fevers 
and  inflammations  of  all  kinds,  attention  to  the  laws  of  health 
will  tend  to  relieve  the  system  from  disease,  more  certainly 
and  speedily,  and  with  less  danger,  than  when  medicines  are 
administered. 

1001.  Thomas  Jefferson,  in  writing  to  Dr.  Wistar,  of  Phil- 
adelphia, said,  "  I  would  have  the  physician  learn  the  limit 
of  his  art."     I  would  say,  Have  the  matrons,  and  those  who 
are  continually  advising  "  herb  teas,"  and  other  "  cure-alls," 
for  any  complaint,  labelled  with  some   popular  name,  learn 
the    limits  of   their  duty,  namely,  attention    to    the  laws  of 
health.     The  rule  of  every  family,  and  each  individual,  should 
be,  to  touch  not,  taste  not  of  medicine  of  any  kind,  except 
when  directed  by  a  well-educated  and  honest  physician,  (sud- 
den disease  from  accidents  excepted.) 

999.  What  is  said  of  the  use  of  medicine  ?  1000.  Of  its  use  in  fever* 
and  many  other  cases  of  disease  ?  1001.  What  remark  by  Thomas  Jeffer- 
son to  Dr.  Wistar  ?  What  should  matrons  learn  ?  What  should  be  th« 
rule  of  every  person  in  regard  to  taking  medicine  ?  What  exception  * 


422  ANATOMY.    PHYSIOLOGY,    AND    HYGIKNE. 


CHAPTER    XLIX. 

DIRECTIONS    FOE,    NURSES. 

1002.  THE    nurse   requires    knowledge   and    practice    to 
enable  her  to  discharge  aright   her  duty  to  the   patient,  as 
much  as  the  physician   and  surgeon  do  to  perform  what  is 
incumbent   on   them.      Woman,  from    her   constitution   and 
habits,  is  the  natural  nurse  of  the  sick;  and,  in  general,  no 
small   portion  of  her   time    is   spent   in   ministering   at   the 
couch  of  disease  and  suffering. 

1003.  As  the  j'Oung  and  vigorous,  as  well  as  the  aged  and 
the  infirm,  are  liable  to  be  laid  upon  the  bed  of  sickness,  by  an 
epidemic,  or  imprudent  exposure,  or  by  some  accident,  it  is 
therefore  necessary  that  the  girl,  as  well  as  the  matron,  may 
know  how  she  can  render  services  in  an  efficient  and  proper 
manner.     No  girl  should  consider  her  education  complete 
who  is  not  acquainted  with  the  principles  of  the  duties  of  a 
general  nurse  and  a  temporary  watcher. 

1004.  It  is  to  be   regretted,  that  while  we  have  medical 
schools  and  colleges  to  educate  physicians,  there  is  no  institu- 
tion to  educate  nurses  in  their  equally  responsible  station.     In 
the  absence  of  such  institutions,  the  defect  can  be  remedied, 
to  some  extent,  by  teaching  every  girl  hygiene,  or  the  laws  of 
health.     To  make  such  knowledge  more  available  and  com 
plete,  attention  is  invited  to  the  following  suggestions  relative 
to  the  practical  duties  of  a  nurse. 

1002.  Does  the  nurse  require  knowledge  and  practice  in  her  employment, 
%s  well  as  the  physician  ?  Who  is  the  natural  nurse  of  the  sick  ? 
K>()3.  What,  then,  is  incumbent  on  every  girl?  1004.  Should  there  l>e 
school*  to  educate  nurses,  as  well  as  physicians  and  surgeons? 


DIRECTIONS    FOR    NURSES. 

1005  BATHING.  The  nurse,  before  commencing  to  bathe 
he  patient,  should  provide  herself  with  water,  two  towels,  a 
sponge,  a  piece  of  soft  flannel,  and  a  sheet.  The  temperature 
of  the  room  should  also  be  observed. 

1006.  When   the   patient    is    feeble,  use    tepid    or   wf.rm 
water.     Cold  water  should  only  be  used  when  the  system  has 
vigor  enough  to  produce  reaction  upon  the  skin.     This  is 
shown  by  the  increased  redness  of  the  skin,  and  a  feeling  of 
warmth   and   comfort,   after   a    proper   amount   of   friction. 
Before  using  the  sponge  to  bathe,  a  sheet,  or  fold  of  cloth, 
should  be  spread  smoothly  over  the  bed,  and  under  the  patient, 
to  prevent  the  bed-linen  on  which  the  patient  lies  from  becom- 
ing damp  or  wet. 

1007.  Apply  the  wet  sponge  to  one  part  of  the  body  at  a 
time  ;  as  the  arm,  for  instance.     By  doing  so,  the  liability  of 
contracting  chills  is  diminished.     Take  a  dry,  soft  towel,  wipe 
the  bathed  part,  and  follow  this  by  vigorous  rubbing  with  a 
crash  towel,  or,  what  is  better,  a  mitten  made  of  this  material ; 
then  use  briskly  a  piece  of  soft  flannel,  to  remove  all  moisture 
that  may  exist  on  the  skin,  and  particularly  between  the  fingers 
and  the  flections  of  the  joints.     In  this  manner  bathe  the  entire 
body. 

1008.  The  sick  should  be  thoroughly  bathed,  at  least  twice 
in  twenty-four  hours.     Particular  attention  should   be  given 
to   the  parts  between   the  fingers  and    toes,   and  about  the 
flections  of  the  joints,  as  the  accumulation  of  the  excretions  is 
most  abundant  on  these  parts.     In  bathing,  these  portions  of 
the  system  are  very  generally  neglected.     The  best  time  for 
bathing,  is  when  the  patient  feels  most  vigorous,  and  freest 
from    exhaustion.     The    practice    of  daubing   the    face    and 
hands  with  a  towel  dipped  in  hot  rum,  camphor,  and  vinegar, 

1006.  "What  should  a  nurse  provide  herself  with,  before  bathing  a  patient  ? 
1006.  When  should  cold  water  be  used?  1007.  How  should  thebathi:.<* 
then  be  performed;  so  that  the  patient  may  not  contract  a  <•">!,•!  ?  1008.  I!  <<v 
often  should  a  sick  persoii  be  bnt'aed  ?  What  is  said  ul  d.iub.ug  tiie  lac* 
and  liauds  merely  -vith  -A  wet  cloth  ? 


434  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

Hoes  not  remove  the  impurities,  but  causes  the  skin  soon  to 
feel  dry,  hard,  and  uncomfortable. 

1009.  FOOD.     It  is  the  duty  of  every  woman  to  know  how 
to  make  the  simple  preparations  adapted  to  a  low  diet,  in  the 
most  wholesome  and  the  most  palatable  way.     Water-gruel,* 
which  is  tx.e  simplest  of  all  preparations,  is  frequently  so  ill- 
made  as  to  cause  the  patient  to  loathe  it.     Always  prepare  the 
food  for  the  sick,  in  the  neatest  and  most  careful  manner. 

1010.  When  the  physician  enjoins  abstinence  from  food, 
the  nurse  should  strictly  obey  the  injunction.     She  should  be 
as  particular  to  know  the  physician's  directions  about  diet,  as 
in  knowing  how  and  when  to  give  the  prescribed  medicines, 
and  obey  them  as  implicitly. 

1011.  When  a  patient  is  convalescent,  the  desire  for  food 
is  generally  strong,  and  it  often  requires  firmness  and  patience, 
together  with  great  care,  on  the  part  of  the  nurse,  that  the 
food  is  prepared  suitably,  and  given  at  proper  times      The 
physician  should  direct  how  frequently  it  should  be  tuken. 

1012.  PURE  AIR.     It  is  the  duty  of  the  nurse  to  see  that 
not  only  the  room  is  well  ventilated  in  the  morning,  but  that 
fresh  air  is  constantly  admitted  during  the  day.     Great  care 
must  be  taken,  however,  that  the  patient  does  not  feel  the 
current. 

1013.  Bed-linen,  as  well  as  that  of  the  body,  should  be  aired 
every  day,  and  oftener  changed  in  sickness  than  in  health. 
All  clothing,  when  changed,  should  be  well  dried,  and  warmed 
by  a  fire  previous  to  its  being  put  on  the  patient  or  the  bed. 


*  Directions  for  making  the  simple  preparations  for  the  sick  are 
found  in  almost  every  cook-book. 

1009.  Should  every  woman  know  how  to  make  the  simple  preparations 
adapted  to  a  low  diet  ?  1010.  Should  the  nurse  strictly  obey  the  injunc- 
tions of  the  physician  relative  to  food?  1011.  What  period  of  a  person's 
illness  requires  the  most  care  in  regard  to  the  food  ?  1012.  Give  another 
duty  of  the  nurse.  1013.  What  directions  respecting  the  bed-linen  of  th£ 
t'.itient  ?  What  is  necessary  when  there  is  a  change  of  clothing  ? 


DIRECTIONS    FOR    NURSES.  435 

1014.  TEMPERATURE.     The  warmth  of  the  chamber  should 
he    carefully  watched  by  the    nurse.     The   feelings    of    the 
patient  or  nurse  are  not  to  be  relied  on  as  an  index  of  the 
temperature  of  the  room.     There  should  be  a  well-adjusted 
thermometer  in  every  sick-room.     This  should  be  frequently 
consulted  by  the  nurse. 

1015.  The   temperature    of  the   sick-chamber   should    De 
moderate.     If  it  is  so  cold  as  to  cause  a  chill,  the  disease  will 
be  aggravated.     If,  on  the  other  hand,  it   is  too  warm,  ,he 
patient  is  enfeebled  and  rendered  more  susceptible  to  cold  on 
leaving  the    sick-chamber.      The   Latin  maxim,  "  In  media 
tutissimus  ibis,"  (in  medium  there  is  most  safety,)  should  be 
regarded  in  the  rooms  of  the  sick. 

1016.  QUIET.    The  room  of  the  patient  should  be  kept  free 
from  noise.     The  community  should  be  guided  by  this  rule, 
that  no  more  persons  remain  in  the  room  of  the  sick,  than  the 
welfare  of  the  patient  demands.     It  is  the  duty  of  the  physi- 
cian to  direct  when  visitors  can  be  admitted  or  excluded  from 
the  sick-room,  and  the  nurse  should  see  that  these  directions 
are  enforced. 

1017.  The  movements  of  the  attendants  should  be  gentle  and 
noiseless.     Shutting  doors  violently,  creaking  hinges,  and  all 
unnecessary  noise,  should  be  avoided.     Most  persons  refrain 
from  loud  talking  in  the  sick   chamber,  but  are  not  equally 
careful  to  abstain  from  whispering,  which  is  often  more  trying 
than  a  common  tone. 

1018.  It  is  the  duty  of  the  nurse  to  ascertain  the  habits 
of  the   patient  as  respects  the   period  for  eating  and  sleep, 
when  in  health,  that  she  may  prepare  the  food  and  arrange 
the  sick-room  in  accordance  with  the  practice  of  the  patient. 

10H.  Why  should  there  be  a  well-adjusted  thermometer  in  every  sick- 
chamber  ?  1015.  What  is  said  of  the  temperature  of  the  sick-chamber  ? 
1016.  Why  should  the  sick-room  be  kept  quiet  ?  1017.  What  is  said  of 
noise  in  the  sick-chamber?  Of  whispering  ?  1018.  Should  the  habits  of 
the  patient  be  regarded  in  reference  to  the  period  for  eating  and  sleen  ? 


436  ANATOMY,    PHYSIOLOGY,    AND    HYGIENE. 

[f  the  person  who  is  sick  is  ignorant  of  the  necessity  of  the 
removal  of  the  waste  products  from  the  system,  the  nurse 
should  invite  attention  to  these  functions  at  such  periods  as 
are  in  accordance  with  the  previous  habits  of  the  patient. 

1019.  The  deportment  and   remarks  of  the  nurse  to  the 
patient  should  be  tranquil  and  encouraging.     The  illness  of  a 
friend,  or  persons  who  have  recently  died,  should  not  be  alluded 
to    in   the   sick-room.     No    doubts  or  fears  of  the   patient's 
recovary,  either  by  a  look  or  by  a  word,  should  be  communi- 
cated by  the  nurse  in  the  chamber  of  the  sick.     When  such 
information  is  necessary  to  be  communicated,  it  is  the  duty  of 
the  physician  to  impart  it  to  the  sick  person. 

1020.  The  nurse  should  not  confine  herself  to  the  sick- 
room more  than  six  hours  at  a  time.     She  should  eat  her  food 
regularly,  sleep  at  regular  periods,  and  take  exercise  daily  in 
the  open  air.     To  do  this,  let  her  quietly  leave  the  room  when 
the  patient  is  sleeping.     A  watcher,  or  temporary  nurse,  may 
supply  her  place.     There  is  but  little  danger  of  contracting 
disease,  if  the  nurse  attends  to  the  simple  laws  of  health,  and 
remains  not  more  than  six  hours  at  a  time  in  the  sick-room. 


DIRECTIONS    FOR   WATCHERS. 

1021.  These  necessary  assistants,  like  the  nurse,  should 
have  knowledge  and  practice.    They  should  ever  be  cheerful, 
kind,  firm,  and  attentive  in  the  presence  of  the  patient. 

1022.  A  simple,  nutritious  supper  should  be  eaten  before 
entering  the  sick-room;  and  it  is  well,  during  the  night,  to 
take  some  plain  food. 

1019.  What  should  be  the  deportment  of  the  nurse  toward  the  patient  ? 
Should  doubts  and  fears  of  the  patient's  recovery  be  communicated  in  the 
sick-room  ?  When  necessary  to  impart  such  intelligence,  on  whom  does  it 
depend  ?  1020.  How  long  should  a  nurse  remain  in  the  sick-chamber  at  a 
time  ?  1021.  What  qualifications  are  necessary  in  a  watcher  ?  1022.  What 
directions  in  regard  to  the  food  of  the  watcher  ? 


D1KKCTJONS    FOR    WATCHERS.  43*7 

1023.  When  watching  in  cold  weather,  a  person  snouid  he 
warmly  dressed,  and  furnished  with  an  extra  garment,  as  a 
cloak  or  shawl,  because  the  system  becomes  exhausted  toward 
morning,  and  less  heat  is  generated  in  the  body. 

1024.  Light-colored  clothing  should  be  worn  by  those  who 
have  care  of  the  sick,  in  preference  to  dark-colored  apparel ; 
particularly  if  the  disease  is  of  a  contagious  character.     Ex- 
periments have  shown,  that  black  and  other  dark  colors  will 
absorb  more  readily  the  subtile  effluvia  that  emanate  from 
sick  persons,  than  white  or  light  colors. 

1025.  Whatever  may  be  wanted  during  the  night,  should 
be  brought  into  the  sick-chamber,  or  the  adjoining  room,  be- 
fore the  family  retires  for  sleep,  in  order  that  the  slumbers  of 
the  patient  be  not  distuioed  by  haste,  or  searching  for  needed 
articles. 

1026.  The  same  general  directions  should  be  observed  by 
watchers,  as  are  given  to  the  nurse  ;  nor  should  the  watchei 
deem  it  necessary  to  make  herself  acceptable  to  the  patient 
by  exhausting  conversation. 

1027.  It  can  hardly  be  expected   that  the  farmer,  who  has 
been  laboring  hard   in  the  field,  or  the  mechanic,  who  has 
toiled  during  the  day,  is  qualified  to  render  all  those   little 
attentions  that  a  sick  person  requires.    Hence,  would  it  not 
be  more  benevolent  and  economical  to  employ  and  pay  watch- 
ers, who  are  qualified  by  knowledge  and  training,  to  perform 
this  duty  in  a  faithful  manner,  while  the  kindness  and  sympa- 
thy of  friends  may  be  practically  manifested  by  assisting  to 
defray  the  expenses  of  these  qualified  and  useful  assistants  ? 

1023.  "When  watching  in  cold  weather,  what  precaution  is  necessary  ? 
1024.  What  is  said  relative  to  the  color  of  the  clothing  worn  in  the 
sick-room  ?  1025.  What  suggestions  to  watchers  relative  to  the  arranse 
ment  of  the  sick-chamber  ?  1026.  What  should  watchers  observe  ? 
1027.  What  is  said  of  employing  those  persons  to  watch  who  labor  hard 
during  the  day  ? 

37* 


APPENDIX. 


POISONS    AND    THEIR    ANTIDOTES 

1028.  POISONING,  either  from  accident  or  design,  is  of  such  frequencj 
and  danger,  that  it  is  of  the  greatest  importance  that  every  person  should 
know  the  proper  mode  of  procedure  in  such  cases,  in  order  to  render  imme- 
diate assistance  when  within  his  power 

1029.  Poisons  are  divided  into  two  classes  —  mineral  (which  include  the 
acids)  and  vegetable. 

1030.  The  first  thing,  usually,  to  be  done,  when  it  is  ascertained  that  a 
poison  has  been  swallowed,  is  to  evacuate  the  stomach,  unless  vomiting 
takes  place  spontaneously.     Emetics  of  the  sulphate  of  zinc,  (white  vitriol,) 
or  ipecacuanha,  (ipecac,)  or  ground  mustard  seed,  should  be  given. 

1031.  When  vomiting  has  commenced,  it  should  be  aided  by  large  and 
frequent  draughts  of  the  following  drinks :  flaxseed  tea,  gum-water,  slip 
pery-elm  tea,  barley  water,  sugar  and  water,  or  any  thing  of  a  mucilaginous 
or  diluent  character. 

MINERAL   POISONS. 

1032.  AMMONIA.  —  The  water  of  ammonia,  if  taken  in  an  over-dose,  and 
in  an  undiluted  state,  acts  as  a  violent  corrosive  poison. 

1033.  The  best  and  most  effectual  antidote  is  vinegar.    It  should  be 
administered  in  water,  without  delay.     It  neutralizes  the  ammonia,  and 
renders  it  inactive.    Emetics  should  not  be  given. 

1034.  ANTIMONY.  —  The  wine  of  antimony  and  tartar  emetic,  if  taken  in 
over-doses,  cause  distressing  vomiting.     In  addition  to  the  diluent,  muci- 
laginous drinks,  give  a  tea-spoonful  of  the  sirup  of  poppies,  paregcric.  or 

1028.  Is  it  useful  to  know  the  antidotes  or  remedies  for  poison?  1029.  Into  how 
many  classes  are  poisons  divided  ?  1030.  What  is  the  first  thing  to  he  done  when  it  is 
ascertained  that  poison  has  been  swallowed?  1031.  What  should  be  taken  after 
the  vomiting  has  commenced?  1032.  What  effect  has  an  over-dose  of  ammonia: 
1033.  The  antidote  ?  Should  an  emetic  be  given  for  this  poison  ?  1034.  What  eflec' 
nas  an  ovei-dosc  of  the  wine  of  antimony  or  tartar  emetic  i 


4-10  APVJ:M»IX. 

1         ty  drops  of  laudanum,  every  twenty  minutes,  until  lm>  or  six   rh >•»«.» 
Jj.ive  been  taken,  or  the  vomiting  ceases. 

1035.  The  antidotes  are  nutgalls  and  oak  bark,  which  may  be  inlniims- 
tered  in  infusion,  or  by  steeping  in  water. 

1036.  A&SENIC.  —  When  this  has  been  taken,  administer  an  emetic  of 
ipecac,  speedily,  in  mucilaginous  teas,  and  use  the  stoinach-puiup  as  soon 
as  possible. 

l-;37.  The  antidote  is  the  hydrated  peroxide  of  iron.  It  should  be  kept 
constantly  on  hand  at  the  apothecaries'  shops.  It  may  be  given  in  any 
qaantity,  without  injurious  results. 

1038.  COPPER.  —  The  most  common  cause  of  poisoning  from  this  metal, 
is  through  the  careless  use  of  cooking  utensils  made  of  it,  on  which  the 
cu-t-ifi-ic  of  copper  (verdigris)  has  been  allowed  to  form.     When  this  has  been 
tsk'.-n,   immediately  induce   vomiting,   give   mucilaginous   drinks,  or  the 
if /tite  of  eggs,  diffused  in  water. 

1039.  The  antidote  is  the  carbonate  of  soda,  which  should  be  administered 
without  delay. 

1040.  LEAD.  —  The  acetate  (sugar)  of  lead  is  the  preparation  of  this  metal, 
which'  is  liable  to  be  taken  accidentally,  in  poisonous  doses.     Induce  imme- 
diate vomiting,  by   emetics  of  ground  mustard  seed,  sulphate  of  zinc,  and 
diluent  drinks. 

1041.  The  antidote  is  diluted  sulphuric  acid.     When  this    acid  is  not  to  be 
obtained,  either  the  sulphate  of  magnesia,  (epsom  salts.)  o»-  the  sulphate  ot 
soda,  (giauber's  Aalts,)  will  answer  every  purpose. 

1042.  MERCURY.  —  The  preparation  of  this  mineral  by  which  poisoning 
is  commonly  JtfOduced,  is  corrosive  sublimate.     The  mode  ot  treatment  to 
be  pursued  when  this  poison  has  been  swallowed,  is  as  follows  :    The  whites 
of  a  dozen  eggs  should  be  beaten  in  two  quarts  of  cold  water,  and  a  tumblpr- 
full  given  every  two  minutes,  to  induce  vomiting.     When  the  whites  of 
eggs  are  not  to  be  obtained,   soap  and  water  should  be  mixed  with  when} 
flour,  and  given  in  copious  draughts,  and   the  stomach-pump  introduced 
as  soon  as  possible.     Emetics  or  irritating  substances  should  not  be  given. 

1043.  NITRE  —  Saltpetre.  — This,  in  over-doses,  produces  violent  poison- 
ous symptoms.     Vomiting  should  be  immediately  induced  by  large  doses 


1035  What  is  the  antidote  ?  1036.  What  should  immediately  be  done  when  arsenic 
is  swallowed?  1037.  What  is  the  antidote?  Can  any  quantity  of  this  preparation  of 
iron  he  given  without  injurious  results?  1038.  What  should  be  given  when  verdi»r>.v 
oas  been  taken  into  the  stomach?  1039.  What  is  the  antidote ?  1010.  What  shun!.) 
immediately  be  given  when  siijrar  of  lead  is  taken?  1041.  What  is  the  antid  n  : 
IM1.  (iive  the  trr.-inneit  \\hei:  corrosive  snblinnte  ha«  hern  swallowed.  104:). 
ctrert  has  an  ove.r  d.'.su  ••!'  s.;it{>ctru  ?  What  treatment  should  IK;  adopted? 


APPENDIX.  411 

of  mujilaginous,  diluent  drinks;  but  emetics  which  irritate  the  stomach 
should  not  be  given. 

1044.  ZINC.  —  Poisoning  is  sometimes  caused  by  the  sulphate  of  zinc* 
(white  vitriol.)     When  this  takes  place,  vomiting  should  be  induced,  and 
aided  by  large  draughts  of  mucilaginous   and   diluent   drinks.     Use  the 
stomach-pump  as  soon  as  possible. 

1045.  The  antidote  is  the  carbonate,  or  super-carbonate  of  soda. 

1046.  NITRIC,  (aqua  fortis,)  MURIATIC,  (marine  acid,)  or  SULPHURIC 
(oil  of  vitriol,)  ACIDS,  may  be  taken  by  accident,  and  produce  poisonous 
effects. 

1047.  The  antidote  is  calcined  magnesia,  which  should  be  freely  admin- 
istered, to  neutralize  the  acid  and  induce  vomiting.     When  magnesia  can- 
not be  obtained,  the  carbonate  of  potash  (salseratus)  may  be  given.     Chalk. 
powdered  and  given  in  solution,  or  strong  soap  suds,  will  answer  a  good 
purpose,  when  the  other  articles  are  not  at  hand.     It  is  of  very  great  im- 
portance that  something  be  given  speedily,  to  neutralize  the  acid.     One  of 
the  substances  before  mentioned   should  be  taken  freely,  in  diluent  and 
mucilaginous  drinks,  as  gum-water,  milk,  flaxseed,  or  slippery-elm  tea. 
Emetics  ought  to  be  avoided. 

1048.  OXALIC  ACID. — This  acid  resembles  the  sulphate  of  magnesia, 
(epsom  salts,)  which  renders  it  liable  to  be  taken,  by  mistake,  in  poisonous 
doses.     Many  accidents  have  occurred  from  this  circumstance.     They  can 
easily  be   distinguished  by  tasting  a  small  quantity.     Epsom  salts,  when 
applied  to  the  tongue,  have  a  very  bitter  taste,  while  oxalic  acid  is  in- 
tensely sour. 

1049.  The  antidote  is  magnesia,  between  which  and  the  acid  a  chemical 
action  takes   place,  producing   the   oxalate  of  magnesia,  which  is  inert. 
When  magnesia  is  not  at  hand,  chalk,  lime,  or  carbonate  of  potash,  (sakera- 
tus,)  will  answer  as  a  substitute.     Give  the  antidote  in  some  of  the  muci- 
laginous drinks  before  mentioned.     No  time  should  be  lost  in  introducing 
the  stomach-pump  as  soon  as  a  surgeon  can  be  obtained. 

1050.  LET.  —  The  ley  obtained  by  the  leaching  of  ashes  may  be  taken 
by  a  child  accidentally.     The  antidote  is  vinegar,  or  oil  of  any  kind.     The 
vinegar  neutralizes  the  alkali  by  uniting  with  it,  forming  the  acetate  of 
potash.     The  oil  'mites  with  the  alkali,  and  forms  soap,  which  is  less  onus- 
tic  than  the  ley.     Give,  at  the  same  time,  large  draughts  of  mucilaginous 
drinks,  as  flaxseed  tea,  &c. 

1044.  What  is  the  antidote  for  white  vitriol?  1047.  What  is  the  antidote  for  ;i(iua 
fortis  and  oil  of  vitriol?  Should  empties  be  avoided?  1048.  How  can  oxalic  urid  ho 
distinguished  from  epsom  salts  ?  1049.  What  is  the  antidote  for  an  over-doso  of  ox- 
alic, acid?  When  magnesia  cannot  he  obtained,  what  will  answer  an  a  substitute  . 
10.,".  What,  is  the  antidote  when  lev  is  swallowed? 


442  APPENDIX. 


VEGETABLE    POISONS. 

1051.  The  vegetable  poisons  are  quite  as  numerous,  and  many  of  them 
equally  as  virulent,  as  any  in  the  mineral  kingdom.     We  shall  describe  the 
most  common,  and  which,  therefore,  are  most  liable  to  be  taken. 

1052.  OPIUM.  —  This  is  the  article  most  frequently  resorted  to  by  those 
wishing  to  commit  suicide,  and,  being  used  as  a  common  medicine,  is  easily 
obtained.     From  this  cause,  also,  mistakes  are  very  liable  to  be  made,  and 
accidents  result  from  it.     Two  of  its  preparations,  laudanum  and  paregoric, 
are  frequently  mistaken  for  each  other ;  the  former  being  given  when  the 
latter  is  intended. 

1053.  Morphia,  in  solution,  or  morphine,  as  it  is  more  commonly  called 
by  the  public,  is  a  preparation  of  the  drug  under  consideration,  with  which 
many  cases  of  poisoning  are  produced.     It  is  the  active  narcotic  principle 
of  the  opium ;  and  one  grain  is  equal  to  six  of  this  drug  in  its  usual  form. 

1054.  When  an  over-dose  of  opium,  or  any  of  its  preparations,  has  been 
swallowed,  the  stomach  should  be  evacuated  as  speedily  as  possible.     To 
efi'ect  this,  a  teaspoonful  of  ground  mustard  seed,  or  as  nmch  tartar  emetic  as 
can  be  held  on  a  five  cent  piece,  or  as  much  ipecacuanha  as  can  be  held  on  a 
twenty-five  cent  piece,  should  be  mixed  in  a  tumbler  of  warm  water,  and 
one  half  given  at  once,  and  the  remainder  in  twenty  minutes,  if  the  first  has 
not.  in  the  mean  time,  operated.     In  the  interval,  copious  draughts  of  warm 
water,  or  warm  sugar  and  water,  should  be  drank. 

1055.  The  use  of  the  stomach-pump,  in  these  cases,  is  of  the  greatest 
importance,  and  should  be  resorted  to  without  delay.     After  most  of  the 
poison  has  been  evacuated  from  the  stomach,  a  strong  infusion  of  coffee 
ought  to  be  given ;  or  some  one  of  the  vegetable  acids,  such  as  vinegar, 
or  lemon-juice,  should  be  administered. 

1056.  The  patient  should  be  kept  in  motion,  and  salutary  effects  will 
often  be  produced  by  dashing  a  bucket  of  cold  water  on  the  head.     Arti- 
ficial respiration  ought  to  be  established,  and  kept  up  for  some  time.     If 
the  extremities  are  cold,  apply  warmth  and  friction  to  them.     After  the 
poison  has  been  evacuated  from  the  stomach,  stimulants,  as  warm  wine  and 
water,  or  warm  brandy  and  water,  should  be  given,  to  keep  up  and  sustain 
vital  action. 

1057.  STRAMONIUM—  Thorn- Apple.  —  This  is  one  of  the  most  active 
narcotic  poisons,  and,  when  taken  in  over-doses,  has,  in  numerous  in- 
stances, caused  death. 

1051.  Are  vegetable  poisons  as  numerous  and  as  virulent  in  their  effects  as  mineral  : 
1052.  What  \s  said  of  opium  and  its  preparations?  1054,  1055,  105G.  What  treutmeui 
vhouli'  be  adopted  when  an  over-dose  of  opium  or  any  of  ita  preparations  is  taken . 
1057.  What  is  -said  of  stramonium? 


APPENDIX.  44,'i 

1058.  HYOSCIAMUS  —  Henbane. — This  article,  which  is  used  as  a  medi- 
cine, if  taken   in   improper  doses,  acts  as  a  virulent  irritating  and  liar 
cotic  poison. 

1059.  The  treatment  for  the  two  above-mentioned  articles  is  similar  to 
that  of  poisoning  from  over-doses  of  opium. 

1060.  CONIUM  —  Hemlock.  —  Hemlock,  improperly  called,  by  many,  cicuta, 
when  taken  in  an  over-dose,  acts  as  a  narcotic  poison.     It  was  by  this 
narcotic  that  the  Athenians  used  to  destroy  the  lives  of  individuals  con- 
demned to  death  by  their  laws.     Socrates  is  said  to  have  been  put  to  death 
by  this  poison.    When  swallowed  in  over-doses,  the  treatment  is  similar 
to  that  of  opium,  stramonium,  and  henbane,  when  over-doses  are  taken. 

1061.  BELLADONNA  —  Deadly   Nightshade.  —  CAMPHOR.      ACONITE  — 
Monkshood,    Wolfsbane.       BRYONIA  —  Bryony.       DIGITALIS  —  Foxglove. 
DULCAMARA  —  Bittersweet.       GAMBOGE.       LOBELIA  —  Indian    Tobacco. 
SANGUINARIA  —  Bloodroot.       OIL    OP    SAVIN.        SPIGELIA  —  Pinkroot. 
STRYCHNINE  —  Nux   vomica.     TOBACCO.  —  All  of  these,  when  taken  in 
over-doses,  are   poisons   of  greater  or  less  activity.     The  treatment  of 
poisoning,  by  the  use  of  any  of  these  articles,  is  similar  to  that  pursued 
in  over-doses  of  opium.     (See  OPIUM,  page  442.) 

1062.  In  all  cases  of  poisoning,  call  a  physician  as  soon  as  possible. 

1058.  Of  henbane?  1059.  What  should  be  the  treatment  when  an  over-dose  of 
rtramonium  or  henbane  is  taken?  1060.  What  name  is  sometimes  improperly  given  te 
ionium,  or  hemlock?  How  was  this  narcotic  poison  used  by  the  Athenians?  How  are 
the  effects  of  an  over-dose  counteracted  ?  1061.  What  is  the  treatment  when  an  over- 
dose of  deadly  nightshade,  monkshood,  foxglove,  bittersweet,  gamboge,  lobelia,  bloodroot, 
tobncco,  &c.,  13  taken?  1062  Should  a  physician  be  called  in  all  cases  when  poisoi 
U  swallowed  ! 


444  APPENDIX. 


Tne  essential  parts  of  every  secretory  apparatus  are  a  simple  membrane, 
apparently  textureless,  named  the  primary,  or  basement  membrane,  certain 
tells  and  blood-vessels.  The  serous  and  mucous  membrane  are  examples. 

B. 

The  division  and  description  of  the  different  membranes  and  tissues  are 
not  well  defined  and  settled  by  anatomical  writers.  This  is  not  a  material 
defect,  as  a  clear  description  of  the  different  parts  of  the  system  can  l*s 
given  by  adopting  the  arrangement  of  almost  any  writer. 

c. 

FAT  is  one  of  the  non-nitrogenous  substances.  It  forms  the  essential 
part  of  the  adipose  tissue.  Chemical  analysis  shows  that  all  fatty  sub- 
stances are  compounds  of  carbon,  hydrogen,  and  oxygen.  They  are  lighter 
than  water,  generally  fluid  at  the  natural  temperature  of  the  body,  and  burn 
with  a  bright  flame,  forming  water  and  carbonic  acid. 

CASEIN E  is  abundantly  found  in  milk.  When  dried,  it  constitutes  cheese 
Alcohol,  acids,  and  the  stomach  of  any  of  the  mammalia  coagulate  it  5  and 
it  is  also  soluble  in  water.  It  is  found  in  the  blood,  bile,  saliva,  and  the 
lens  of  the  eye. 

CHONDRINE  is  a  variety  of  gelatin.  It  is  obtained  from  cartilage.  It 
is  soluble  in  warm  water,  but  solidifies  on  cooling. 

LACTIC  ACID  is  common  to  all  the  solids  and  fluids  of  the  system.  It  is 
found  united  with  potash,  soda,  lime,  or  magnesia. 

D. 

The  word  duodenum  is  derived  from  the  Latin,  signifying  "  twelve,"  since 
the  intestine,  of  which  this  is  the  name,  is  usually  about  twelve  fingers'  breadth 
in  length.  The  jejunum  is  also  from  the  Latin  Jejunu.!,  empty,  since  it  is 
usually  found  in  that  condition  after  death,  as  the  food  seems  to  pass  rapidly- 
through  this  part  of  the  intestine.  The  term  ileum  is  from  the  Greek,  signi- 
fying "  to  twist,"  since  it  always  appears  in  a  contorted  cc  ndition.  The  name 
crpcum  is  derived  from  the  fact  of  its  being  a  blind  or  short  sack,  perforated 
by  the  extremity  of  the  ileum.  The  name  of  the  next  division  of  the  intes- 
tine—  colon — is  from  the  Greek,  "to  prohibit,"  as  the  contents  of  the  ali- 
mentary canal  pass  slowly  through  this  portion.  The  rectum  is  named  frmr 
ihe  straight  direction  '.hat  it  assumes  in  the  latter  part  of  its  course 


445 


E. 

The  food  is  forced  through  the  alimentary  canal  by  contractions  of  itt 
muscular  coat,  produced  by  the  nervous  filaments  of  the  sympathetic  sys 
vein,  not  being  at  all  dependent  on  the  cerebro-spinal  centre.  This  is  calle< 
the  peristaltic,  or  vermicular  motion.  The  great  length  o'  intestine  in  a. 
animals,  and  especially  in  the  herbivorous  ones,  is  owing  to  the  necessity  of 
exposing  the  food  to  a  large  number  of  the  lacleals,  that  the  nourishment  ma} 
all  be  taken  from  it. 

F. 

The  different  processes  through  which  the  food  passes  before  assimilation 
are  of  considerable  interest.  The  mastication  and  mixture  of  the  saliva 
with  the  food  are  purely  of  a  mechanical  nature.  When  any  solid  or  fluid 
substance  is  placed  upon  the  tongue,  or  in  contact  with  the  inner  surface  of 
>.he  checks,  by  an  involuntary  act,  the  salivary  glands  are  stimulated  tc 
activity,  and  commence  pouring  the  saliva  into  the  mouth  through  the  sali- 
vary ducts.  As  soon  as  mastication  commences,  the  contraction  of  the 
masseter  and  other  muscles  employed  in  mastication  stimulates  the  salivary 
glands  to  increased  action,  and  a  still  greater  quantity  of  saliva  is  secreted 
and  forced  upon  the  food,  which  is  constantly  being  ground  to  a  finer  con- 
dition, until  it  is  sufficiently  reduced  for  deglutition. 

Whether  the  salivary  fluid  acts  any  other  part  than  simply  that  of  a  de 
mulcent  to  assist  the  gastric  juice  in  still  further  dissolving  the  food,  is  yet  a 
matter  of  some  doubt,  although  it  is  found  that  no  other  liquid  will  equalh 
well  subserve  the  process  of  digestion  and  promote  health. 

After  the  food  is  in  the  condition  ready  to  be  swallowed,  by  an  apparently 
involuntary  motion,  it  is  placed  upon  the  back  of  th«  ^ngue,  which  carrier 
H  backwards  to  the  top  of  the  pharynx,  where  the  constrictions  of  the 
pharynx,  aided  by  the  muscles  of  the  tongue  and  floor  of  the  mouth,  with  a 
sudden  and  violent  movement  thrust  it  beyond  the  epiglottis,  in  order  tc 
allow  the  least  necessary  time  to  the  closure  of  the  glottis,  after  which,  by 
ihe  compression  of  the  oasophagus,  it  is  forced  irr.o  the  stomach. 

Here  it  is  that  the  true  business  of  digestion  comniences.  For  as  soon  aj 
any  substance  except  water  enters  the  stomach,  this  orga^,  w:*h  involuntary 
movements,  that  seem  almost  like  instinct,  commences  the  secretion  of  tin- 
gastric  juice,  and  by  long-continued  contractions  of  its  muscular  coat,  suc- 
ceeds iii  effecting  a  most  perfect  mixture  of  the  food  with  this  juice,  by  which 
the  contents  of  the  stomach  are  reduced  to  the  softest  pulp. 

The  gastric  juice,  in  its  pure  state,  is  a  colorless,  transparent  fluid  ;  "  ino- 
dorous, a  little  saltish,  and  perceptibly  acid.      It  possesses  the  proper v  <M 
albumen,  and  separating  the  whey  of  milk  from  its  c«rd.  >iud 
completely  dissolving  the  curd.      Its  taste,  when  applied   lo  il»r 

38 


446 


APPENDIX. 


tongue,  is  similar  to  that  of  mucilaginous  water,  slightly  acidulated  witfc 
/nuriatic  acid.''  The  organs  of  its  secretion  are  an  immense  number  of 
tubes  or  glands,  of  a  diameter  varying  from  one  five  hundredth  to  one  three 
nundredth  of  an  inch,  situated  in  the  mucous  coat  of  the  stomach,  and  receiv- 
ing their  blood  from  the  gastric  arteries.  A  chemical  analysis  shows  it  to 
consist  of  water,  mucilage,  and  the  several  free  acids  —  muriatic,  acetic, 
lactic,  and  butyric,  together  with  a  peculiar  organic  matter  called  pepsin, 
which  acts  after  the  manner  of  ferments  between  the  temperature  of  50° 
•ad  104°  F. 

The  true  process  of  digestion  is  probably  owing  to  the  action  of  pepsin 
and  the  acids,  especially  if  the  presence  of  the  chloro-hydric  or  muriatic  be 
admitted  ;  since  we  know,  by  experiments  out  of  the  body,  that  chlorine,  one 
of  its  elements,  is  a  powerful  solvent  of  all  organic  substances. 

The  antiseptic  properties  of  the  gastric  juice,  as  discovered  by  experi 
ments  made  on  Alexis  St.  Martin,  doubtless  have  much  influence  on  digestion, 
ilthough  their  true  uses  are  probably  not  yet  known. 

As  soon  as  the  food  is  reduced  to  a  state  of  fluidity,  the  pyloric  orifice 
of  the  stomach  is  unclosed,  and  it  is  thrust  onwards  through  the  alimentary 
canal,  receiving  in  the  duodenum  the  secretions  of  the  liver  and  pancreas, 
after  which  it  yields  to  the  lacteals  its  nutrient  portion,  and  the  residuum  ia 
expelled  from  the  oody. 

There  have  been  many  hypotheses  in  regard  to  the  nature  of  the  digestive 
process.  Some  have  supposed  that  digestion  is  a  mere  mechanical  process, 
produced  by  the  motion  of  the  walls  of  the  stomach  ;  while  others,  in  later 
times,  have  considered  it  as  under  the  influence  of  a  spirit  separate  from  the 
individual,  who  took  up  his  residence  in  the  stomach  and  regulated  the  whole 
affair  ;  while  others  still  would  make  it  out  to  be  a  chemical  operation,  and 
thus  constitute  the  stomach  a  sort  of  laboratory.  But  to  all  these  ridicu- 
lous hypotheses  Sir  John  Hunter  has  applied  the  following  playful  Ian 
guage :  "  Some  will  have  it  that  the  stomach  is  a  mill  5  others  that  it  is  a 
fermenting  vat ;  and  others  that  it  is  a  stewpan  3  but  in  my  view  of  the 
matter,  it  is  neither  a  mill,  a  fermenting  vat,  nor  a  stewpan,  but  a  stomach, 
a  stomach  !  " 

At  the  present  day  this  process  is  regarded  as  a  complex,  and  not  a  simple 
operation.  It  seems  to  be  a  process  in  which  the  mechanical,  chemical,  and 
vital  agencies  must  all  act  in  harmony  and  order ;  for  if  one  of  these  be 
withdrawn,  the  function  cannot  be  sustained  for  any  considerable  length  of 
time  ;  and  of  the  chemical  and  mechanical  parts  of  the  process,  since  the 
former  is  much  more  important,  and,  as  a  matter  of  course,  the  vital  powers 
are  indispensable,  therefore  digestion  may  be  considered  as  a  chemical 
operation,  directly  dependent  on  the  laws  of  vitality,  or  of  life  j  since  the 
proper  consistency  of  the  food  depends,  in  a  great  measure,  upon  the  char- 
acter of  the  solvents,  while  the  secretion  of  these  fluids,  their  proper  amount. 


APPENDIX. 


447 


together  with  the  peculiar  instinct  —  as  it  almost  seems  to  be  —  necessary 
to  direct  the  stomach  in  its  many  functions,  are  exclusively  and  entirely  de 
pendent  on  the  laws  and  conditions  of  life. 


G. 

As  food  is  necessary  to  supply  the  waste  and  promote  the  growth  of  the 
body,  it  follows  that  that  will  be  the  best  adapted  to  the  system  which  con- 
tains the  same  chemical  elements  of  which  the  body  is  composed  5  viz., 
oxygen,  hydrogen,  carbon,  and  nitrogen.  These  elements  are  found  in 
greater  or  less  quantity  in  all  animal  food,  and  in  many  vegetable  products. 
Hence,  that  article  of  food  which  contains  all  these  elements  in  a  proper 
proportion  will  tend  much  more  to  the  growth  and  strength  of  the  body  than 
those  kinds  which  are  deficient  in  one  or  more  of  them.  Much  experience 
on  this  point,  and  scientific  research,  seem  to  show  that  a  reasonaole  amount 
of  animal  food  in  health  tends  to  give  greater  strength  of  muscle,  and  a 
more  general  sense  of  fulness,  than  in  ordinary  cases  a  vegetable  diet  is  able 
to  do,  owing  to  the  presence  of  nitrogen  in  animal  tissues.  Yet  there  are 
examples  of  the  healthiest  and  strongest  men,  who  live  years  without  a 
morsel  of  animal  food  ;  and  the  fact  can  only  be  accounted  for,  by  supposing 
that  the  system  has  the  power  to  make  the  most  economical  use  of  the  little 
nitrogen  offered  to  U  in  the  food  ;  or  else  that  it  has  by  some  means  the 
power  to  abstract  it  from  the  atmosphere,  and  transform  it  to  the  living  ani- 
mal substance. 

H. 

The  proximate  principles,  which  are  the  most  important  in  nourishing  the 
body,  are  albumen  and  fibrin.  These  constitute  the  greater  part  of  all  the 
softer  animal  tissues,  and  are  also  found  in  certain  classes  of  vegetables,  such 
as  peas,  beans,  lentils,  and  many  seeds.  Hence,  in  many  cases,  a  vegetable 
diet,  especially  if  embracing  any  of  these  articles,  would  be  sufficient  to 
sustain  life,  even  if  no  animal  food  should  be  eaten.  But  no  animal  can 
exist  for  a  long  time  if  permitted  only  to  eat  substances  destitute  of  nitrogen, 
as  in  the  case  of  a  dog  fed  entirely  on  sugar,  which  lived  but  thirty  days. 
And  owing  to  ».his  fact,  Baron  Liebig  proposes  to  call  substances  used  for 
food,  containing  nitrogen/'  elements  of  nutmion,"  and  those  containing  an  ex 
cess  of  carbon,  "  elements  of  respiration  ; '^since,  according  to  his  view,  the 
food  is  necessary  to  support  the  growth  of  the  body  by  replacing  the  effete 
and  worn-out  particles  with  new  matter,  and  also  to  keep  up  the  supply  of 
fuel,  in  order  to  promote  a  sufficient  degree  of  heat  in  the  system.  Accord- 
ingly, under  the  first  division  would  be  included  all  lean  meats  and  vegetables, 
lich  as  peas,  &c. ;  while  the  fat  of  animals,  vegetable  oils,  sugars,  tubers, 
as  the  potato,)  and  all  other  substances  containing  starch,  would  be  included 
under  the  latter  division. 


44  ft 


A.PPI  XD1X. 


1. 


This  Definition  of  exhalaats  is  from  the  theory  of  Haller  and  other?  ll 
s  now  believed  that  the  fluids  exude  through  the  thin  coats  of  the  blood 
vessels.  This  process  is  called  exosmose,  and  is  the  exhalation  of  old 
physiologists. 

J. 

It  is  a  well-established  fact,  in  animal  and  vegetable  physiology,  that  mem 
oranes  possess  the  property  of  allowing  fluids  and  gases  to  pass  through 
them  in  either  direction,  and  also  to  permit  two  fluids  to  pass  in  opposite 
directions  at  the  same  time.  This  property  is  designated  endosmose  when  a 
fluid  passes  from  without  a  body  inward  ;  and  exosmose.  when  the  reverse 
takes  place.  The  first  is  called  imbibition.  One  of  the  most  striking  instances 
of  this,  in  the  human  system,  is  shown  in  the  lungs,  where  carbonic  acid  and 
water  pass  out  through  the  mucous  membrane  of  the  bronchial  tubes  and 
air-cells  ;  and  the  oxygen  of  the  air  enters  the  blood  through  the  same  mem- 
brane. By  this  process  of  imbibition,  the  oxygenation  of  the  blood  is  much 
more  readily  and  faithfully  accomplished  j  inasmuch,  as  by  the  immense 
number  of  bronchial  tubes  and  air-cells  a  larger  quantity  of  blood  is  ex- 
posed to  a  greater  portion  of  air,  than  if  the  blood  were  directly  laid  open 
!o  the  atmosphere  in  a  mass,  or  the  air  were  immediately  transmitted 
through  it. 

Since  the  function  of  respiration  is  to  free  the  system  of  superfluous 
carbon  and  hydrogen,  by  union  with  the  oxygen  of  the  air,  it  follows  thai 
the  greater  the  amount  of  the  products  to  be  expelled,  the  larger  the  quan- 
tity of  oxygen  will  be  required  to  effect  this  purpose,  as  we  find  to  be  the 
case  with  those  who  consume  large  quantities  of  food. 

The  quantity  of  oxygen  daily  consumed  through  the  lungs  by  an  adult 
is  about  32.5  oz.,  and  the  carbon  in  the  food  13.9  oz.  But  in  order  to  con- 
vert this  whole  amount  of  carbon  into  carbonic  acid,  which  passes  off  through 
the  lungs  and  skin,  37  oz.  of  oxygen  are  required  j  the  remaining  4.5  oz. 
being  absorbed  by  the  skin.  If  the  supply  of  food  remain  the  same,  while 
the  amount  of  oxygen  in  the  inspired  air  is  diminished,  the  superfluous  cnr- 
boi:  will  induce  disease  in  the  system,  as  is  the  case  of  those  persons  who 
are  limited  in  their  supply  of  air  of  a  proper  quality  or  quantity,  and,  con 
sequenlly,  have  less  appetite  ror  food  than  those  who  are  abundantly  sup- 
plied with  air  of  the  proper  standard  of  health  ;  and  in  children,  who  pro- 
oortionally  consume  more  food  than  adults,  and  who  are  more  active,  thereby 
causing  a  more  rapid  circulation  of  blood,  and.  consequently,  the  removn 
af  more  superfluous  particles  of  matter. 

In  children  we  notice  the  need  of  air,  by  their  disposition  to  b«  much  in  ii;< 
jpen  air,  and  often  inspiring  more  deeply  than  is  common  in  older  per^n* 


Also,  if  (lie  carbon  of  the  fool  does  not  have  <\  requisite  supply  of  OV'V^IM. 
trout  the  air,  or  other  sources,  the  body  becomes  emaciated,  although  nourish 
ing  food  may  be  used.  And  on  the  other  hand,  if  there  be  a  diminished  sup 
ply  of  food,  but  an  abundance  of  atmospheric  air,  leanness  and  emaciation  are 
sure  to  fo.low  ;  owing-  to  the  fact  that  if  the  oxygen  has  no  waste  carbon 
from  the  body  to  unite  with,  it  combines  with  the  fat,  and  some  other  soil 
portions  of  the  body,  which  the  Author  of  nature  seems  to  have  provided 
for  this  very  purpose  5  as  is  seen  in  the  case  of  hibernating  animals,  who 
enter  their  places  of  winter  abode  sleek  and  fat,  but  crawl  out  in  the  spring 
not  merely  deprived  of  their  fatty  matter,  but  also  with  great  diminution  of 
all  the  softer  parts,  which  have  given  up  their  share  of  carbon  to  supply 
animal  heat.  One  important  cause  of  emaciation  in  febrile  diseases  is  liic 
greater  rapidity  of  the  pulse  and  respiration,  which  consume  more  carbon 
than  is  afforded  by  the  scanty  supply  of  food  that  is  taken,  although  profuse 
perspiration,  which  almost  always  occurs  in  some  stages  of  fevers,  greatly 
diminishes  the  full  state  of  the  body. 

K. 

The  theory  of  Baron  Liebig  concerning  the  change  which  the  blood 
experiences  in  color,  in  its  passage  through  the  lungs,  meets  with  the  appro- 
nation  of  many  physiologists,  although  there  are  some  important  difficulties 
in  the  way  of  fully  receiving  it.  A  chemical  analysis  of  the  blood  shows  it 
to  be  composed  of  albumen  and  fibrin,  together  with  some  other  substances. 
in  small  proportions,  and  always  perceptible  traces  of  iron.  He  attributes 
the  change  in  color  to  the  iron,  as  this  substance  enters  into  combination 
with  carbon  and  oxygen.  For,  as  the  blood  passes  through  the  trunks  of 
the  larger  vessels  and  capillaries,  it  receives  the  carbon  from  the  tissues 
which  are  continually  transformed,  and  taking  up  the  oxygen  from  the  aite- 
rialized  blood,  forms  carbonic  acid,  which  unites  with  the  iron,  forming  proto- 
carbonate  of  iron.  This  being  of  a  gray  color,  he  supposes  it  to  be  that 
which,  with  the  other  impurities  of  the  blood,  gives  the  venous  blood  the  dark 
blue  color.  Then,  as  the  blood  comes  in  contact  with  the  oxygen,  as  it  is 
returned  and  exposed  to  this  element  in  the  lungs,  the  carbonic  acid  leaves 
the  iron,  which  has  a  stronger  affinity  for  oxygen  than  for  carbenic  acid,  and 
forms  the  scarlet  red  peroxide  of  iron,  that  gives  the  characteristic  color  to 
Ihe  arterial  blood.  After  this,  as  the  blood  is  sent  out  through  the  smaller 
arteries  and  capillaries,  it  again  gathers  carbon  and  other  impurities  fro-n 
the  system,  and  becomes  the  dark,  venous  blood,  thus  completing  the  whole 
color  in  the  circulation. 

38* 


450  APPENDIX. 


As  already  mentioned,  different  articles  of  food  have  been  divided  mtc 
the  azotized  and  non-azotized,  or  those  which  contain  nitrogen  as  one  of  their 
constituents,  and  those  which  are  nearly  destitute  of  it.  Of  these,  accord- 
ing to  Liebig,  the  azotized  portions  are  simply  to  supply  the  waste  that  is 
continually  going  on  in  the  body,  and  promote  its  growtli  in  the  early  stages 
of  existence,  or,  in  other  words,  the  nutrient  portion  3  while  the  sugar,  starch, 
&c.,  are  mainly  of  use  in  the  respiratory  organs.  The  correctness  of  uiii 
view  may  be  understood  from  the  fact,  that  the  inhabitants  in  the  colder 
regions  of  the  earth  consume  a  much  larger  quantity  of  oil  and  fat  than 
the  residents  of  hotter  climates  ;  and  also  those  dwelling  in  the  temperate 
zones  can  eat  with  greater  impunity  a  larger  quantity  of  fat  meats  in  the 
winter  than  in  the  summer,  there  being  then  so  much  more  demand  for  ani 
nial  heat  than  in  the  summer. 


M. 

The  suggestion  of  using  the  bellows  in  asphyxia,  is  from  the  directions 
of  that  distinguished  and  veteran  surgeon,  Valentine  Mott,  of  New  York 
city.  The  directions  in  the  first  part  of  the  paragraph  are  the  most  prac- 
tical, acJi  best  adapted  to  the  vaults  of  the  community. 


9LOSSARY 


AB-mic'ToF  [I*  «*<h^«  ^ \eadaway.] 
A  niUM-le  v/uicli  iitjves  rntain  parts, 
oy  separating  them  from  vh«  Axis  of  the 
body. 

AB-DO'MEN.  [L.  abdo,  to  hide  ]  That 
part  of  the  body  which  lies  between 
the  thorax  and  the  bottom  of  the 
pelvis. 

AB-DOM'IN-IS.  Pertaining  to  the  ab- 
domen. 

A-CE-TAB'U-LUM.  [L.  acctum,  vinegar.] 
The  socket  for  the  head  of  tie  thigh- 
bone ;  an  ancient  vessel  for  holding 
vinegar. 

A-CE'TIC.  [L.  acctum,  vinegar.]  Relat- 
ing to  acetic  acid.  This  is  always  com- 
posed of  oxygen,  hydrogen,  and  carbon, 
in  the  same  proportion. 

A-CHII/LIS.  A  term  applied  to  the  ten- 
don of  two  large  muscles  of  the  leg. 

A-CRO'MI-ON.  [Gr.  axpos,  akros,  highest, 
and  Muog,  omos,  shoulder.]  A  process 
of  the  scapula  that  joins  to  the  clavicle. 

AD-DUC'TOR.  [L.  adduco,  to  lead  to.] 
A  muscle  which  draws  one  part  of  the 
body  toward  another. 

AL-BU-GIN'E-A.  [L.  albus,  white.]  A 
term  applied  to  white  textures. 

AL-BU'MEN.  [L.  albus,  white.]  An  ani- 
mal substance  of  the  same  nature  as  the 
white  of  an  egg. 

A-LU'MIN-UM.  [L.]  The  name  given 
to  the  metallic  base  of  alumina. 

AL'VE-O-LAR.  [L.  alveolus,  a  socket.] 
Pertaining  to  the  sockets  of  the  teeth. 

AM-MO'NI-A.  An  alkali.  It  is  composed 
of  three  equivalents  of  hydrogen  and 
one  of  nitrogen. 

A-NAS'XO-MOSE.    [Gr.  ava,  ana,  through, 


and  ffTopa,  stoma,  mouth.]  The  com- 
munication of  arteries  and  veins  with 
each  other. 

AN-A-TOM'I-CAL.  Relating  to  the  parts 
of  the  body,  when  dissected  or  sep- 
arated. 

A-NAT'O-MY.  [Greek  ava,  ana,  through, 
and  TOW,  tomS  a  cutting.]  The  de- 
scription of  the  structure  of  animals. 
The  word  anatomy  properly  signifies 
dissection. 

AN'GU-LJ.  [L.  angulus,  a  corner.]  A 
term  applied  to  certain  muscles  on  ac- 
count of  their  form. 

AN-I-MAL'CU-L-E.       [L.    animalcula,   a 
little  animal.]     Animals  that  are  only 
perceptible  by  means  of  a  microscope. 
AN'NU-LAR.    [L.annuZws,  a  ring.]    Hav- 
ing the  form  of  a  ring. 
AN-TI'CUS.    [L.]    A  term  applied  to  cer- 
tain muscles. 

A-ORT'A.     [Gr.  aoprij,  aortS ;  from  aqp, 
aer,  air,  and   r>jpcw,  tSreo,  to    keep.] 
The  great  artery  that  arises  from  the 
left  ventricle  of  the  heart. 
Ap-O-NEU-RO'sis.     [Gr.  ano,  apo,  from, 
and    vsvpov,  neuron,   a    nerve.]      The 
membranous    expansions    of    muscles 
and    tendons.       The    ancients    called 
every  white  tendon  neuron,  a  nerve. 
AP-PA-RA'TUS.     [L.  apparo,  to  prepare.] 
An  assemblage  of  organs   designed  to 
produce  certain  results. 
AP-PEND'IX.     [L.,  an  addition.]    Some- 
thing appended  or  added. 
A'QUE-OUS.      [L.    aqua,   water.]      Par- 
taking of  the  nature  of  water. 
A-RACH'NOID.    [Gr.  apax«"7»  arachnS,  a 
spider,  and  uJoj,  cidos,  form.l      Ro 


GLOSSARY. 


seinhiing  a  spid  *r'a  web.  t  A  thin  mem- 
hrane  Hint  cove'?  the  bruin. 

AR'BOR.  [L.]  A  tree.  Arbor -cite.  The 
tree  of  life.  A  term  applied  to  a  part 
of  the  cerebellum. 

Ail'TE-RY.  [Gr.  arjp,  aSr,  air,  and  TIJOFM, 
tcreo,  to  keep ;  because  the  ancients 
thought  that  the  r\rteries  contained  only 
air.]  A  tube  t'irough  which  blood 
flows  from  the  heart. 

A-RYT-E'NOID.  [Gr.  apvraiva,arutawa, 
a  ewer,  and  et6os,  eidos,  form.]  The 
name  of  a  cartilage  of  the  larynx. 

AS-CEND'ENS.  [L.]  Ascending;  ris- 
ing. 

AS-PHYX'I-A.  [Gr.  a,  a,  not,  and  ff<pv£ts, 
spliyxis,  pulse.]  Originally,  want  of 
pulse  ;  now  used  for  suspended  respira- 
tion, or  apparent  death. 

AS-TRAG'A-LUS.  [Gr.J  The  name  of 
a  bone  of  the  foot.  One  of  the  tarsal 
bones. 

AUD-I'TION.  [L.  audio,  to  hear.]  Hear- 
ing. 

AUD-IT-O'RI-US.  [L.]  Pertaining  to  the 
organ  of  hearing. 

AU'RI-CLE.  [L.  auricula,  the  external 
ear ;  from  auris,  the  ear.]  A  cavity  of 
the  heart. 

Au-Ric'u-LAR.  [L.  auricula.]  Pertain- 
ing *o  the  auricle. 

Ax-ri/LA.    [L.]    The  armpit 

AX'IL-LA-RY.  Belonging  or  relating  to 
the  armpit. 

A-ZOTE'.  [Gr.  a,  a,  not.  and  ^to??,  zo«, 
life.]  Nitrogen.  One  of  the  constit- 
uent elements  of  the  atmosphere.  So 
named  because  it  will  not  sustain  life. 

BEN-ZO'IC.      Benzoic    acid.     A  peculiar 

vegetable  acid,  obtained  from   benzoin 

and  some  other  balsams. 
BI'CEPS.     [L.   bis,  t\\  ice,   and  caput,   a 

head.]    A  name  applied  to  muscles  with 

two  heads  at  one  extremity. 
BI-CUS'PIDS.     [L.  bis  and  cuspis,  a  point.] 

Teeth  that  have  two  points  upon  their 

crown. 
BILE.    [L.  bills.]    A  yellow,  viscid  fluiH 

«ecreted  by  the  liver. 


Bl-PEN'NI-FORM.  [L.  bis  and  penruL,  i 
feather.]  Bipenniform  muscle.  Having 
fibres  on  each  side  of  a  common 
tendon. 

BRACH'I-AL.  [L.  brachium.]  Belonging 
to  the  arm. 

BRE'VIS.  [L.]  Brevis,  short;  brcvior 
shorter. 

BRONCH  I-A,  -JE.  [L.]  A  division  of 
the  trachea  that  passes  to  the  lungs. 

BRONCH'I-AL.     Relating  to  the  bronchia. 

BRONCH-I  TIS.  [L.]  An  inflammation 
of  the  bronchia. 

BUC-CI-NA'TOR.  [L.  buccinuin,  a  trum 
pet.]  The  name  of  a  muscle  of  th* 
cheek,  so  named  because  used  in  blow- 
ing wind  instruments. 

BUR's^E  Alu-CO'SA.  [L.  bursa,  a  purse, 
and  mucosa.  viscous.]  Small  saca. 
containing  a  viscid  fluid,  situated  about 
the  joints,  under  tendons. 

CJR  CUM.  [L.]  Blind  ;  the  name  given 
to  the  commencement  of  the  colon. 

CALX,  CAL'CIS.     [L.J    The  heel-bone. 

CAL'CI-UM.  [L.]  The  metallic  basia 
of  lime. 

CAP'IL-LA-RY.  [L.  capillus,  a  hair. 
Resembling  a  hair  ;  small. 

CAP'SU-LAR.    Pertaining  to  a  capsule. 

CAP'SULE.  [L.  capsula,  a  little  chest.J 
A  membranous  bag,  enclosing  a  part. 

CA'PUT.  [L.]  The  head.  Caput  coli. 
The  head  of  the  colon. 

CAR'BON.  [L.  carbo,  a  coal.]  Pure  char- 
coal. An  elementary  combustible  sub 
stance. 

CAR-BON'IC.    Pertaining  to  carbon. 

CAR'DI-AC.  [Gr.  *a//<5ta,  kardia,  heart.) 
Relating  to  the  heart,  or  upper  orifice 
of  the  stomach. 

CAR'NE-A,  -JE.  [L.  carj,  carnis,  flesh.l 
Fleshy. 

CA-ROT'ID.  [Gr.  icapos,karos,  lethargy.] 
The  great  arteries  of  the  neck  that  con- 
vey blood  to  the  heart.  The  ancients 
supposed  drowsiness  to  be  seated  in 
these  arteries. 

CAR'PAL.  [L.  carpus,  the  wrist.?  Ro 
lating  to  the  wrist. 


GLOSSARY. 


CAR'PUS,  -i.    f L.j    The  wrist. 

•JAR'TI-LAGE.  [L.  cartilago.]  Gristle 
A  smooth,  elastic  substance,  softer  than 
bone. 

CAR-TI-LAG'IN-OUS.  Pertaining  to  car- 
tilage. 

CAU-CA'SIAN.  One  of  the  races  of 
men. 

CA'VA.  [L.]  Hollow.  Vena,  caca.  A 
name  given  to  the  two  great  veins  of 
the  body. 

L'EL/LU-LAR.  [L.  cellula,  a  little  cell.] 
Composed  of  cells. 

(.  EII-E-BEL'LUM.  [L.j  The  hinder  and 
lower  part  of  the  brain,  or  the  little 
brain. 

CER'E-BRAL.    Pertaining  to  the  brain. 

CER'E-BRUM.  [L.]  The  front  and  large 
part  of  the  brain.  The  term  is  some- 
times applied  to  the  whole  contents  of 
the  cranium. 

CER'E-BRO-SPI'NAL.  Relating  to  the 
brain  and  spine. 

CER'VIX.     [L.]    The  neck. 

CER'VI-CAL.    Relating  to  the  neck. 

CHEST.  [Sax.]  The  thorax ;  the  trunk 
of  the  body  from  the  neck  to  the 
abdomen.* 

CHLO'RIME.  [Gr. xAwp''J? chloros, green.] 
Chlorine  gas,  so  named  from  its  color. 

CHOR'DA,  -IE.  [L.]  A  cord.  An  assem- 
blage of  fibres. 

CHO'ROID.  [Gr.  xoptvv,  chorion.]  A 
term  applied  to  several  parts  of  the 
body  that  resemble  the  skin. 

CHVT,E.  [Gr.  x^Aoj,  chulos,  juice.]  A 
nutritive  fluid,  of  a  whitish  appearance, 
which  is  extracted  from  food  by  the 
action  of  the  digestive  organs. 

."HYL-I-FI-CA'TION.  [chyle  and  L./a«'o, 
to  make.]  The  process  by  which  chyle 
is  fonued. 

CHYME.  [Gr.  XD/JOJ,  ckumos,  juice.]  A 
kind  of  grayish  pulp  formed  from  the 
food  in  the  stomach. 

CIIYM-I-FI-OA'TION.  [cJtyme  and  L. 
far.io,  to  make.]  The  process  by  which 
rhyme  is  formed. 

Cu/iA-RY.  [L.  cilia,  eyelashes.]  Be- 
konging  to  thi*  eyelids. 


CIN-E-RI'TIOUS.  [L.  dms,  ashes.]  Hav- 
ing the  colur  of  ashes. 

CLAV'I-CLE.  [L.  claoicula,  from  clari*,  a 
key.]  The  collar-bone  ;  so  called  ('nun 
its  resemblance  in  shape  to  an  ancient 
key. 

CLEI'DO.  A  term  applied  to  some  mus- 
cles that  are  attached  to  the  clavicle. 

CO-AG'U-LUM.  [L.]  A  coagulated  masa, 
a  elot  of  blood. 

COC'CYX.  [Gr.]  An  assemblage  ol 
bones  joined  to  the  sacrum. 

COCH'LE-A.  [Gr.  K«xAu>,  kochh,  to  twist ; 
or  L.  cochlea,  a  screw.]  A  cavity  of  the 
ear  resembling  in  form  a  snail  shell. 

CO'LON.  [Gr.]  A  portion  of  the  large 
intestine. 

CO-LUM'WA,  -M.  [L.]  A  column  or 
pillar. 

COM-MU'NIS.  [L.]  A  name  applied  to 
certain  muscles. 

COM-PLEX'US.  [L.  complector,  to  era. 
brace.]  The  name  of  a  muscle  that 
embraces  many  attachments. 

COM-PRESS'OR.  [L.  con,  together,  and 
premo,  pressus,  to  press.]  A  term  ap- 
plied to  some  muscles,  that  compress 
the  parts  to  which  they  are  attached 

CON'DYLE.  [Gr.  Kov6v\os,  kondulo*,  a 
knuckle,  a  protuberance.]  A  proini 
nence  on  the  end  of  a  bone. 

CON-JUNC-TI'VA.  [L.  con,  together,  and 
jungo,  to  join.]  The  membrane  that 
covers  the  anterior  part  of  the  globe 
of  the  eye. 

COP'PER.  A  metal  of  a  pale,  red  color, 
tinged  with  yellow. 

COR-A'COID.  [Gr.  *o/3a|,  koraz,  a  crow, 
and  etdug,  eidos,  form.]  A  process 
of  the  scapula  shaped  like  the  beak 
of  a  crow. 

CO'RI-OJV.  [Gr.  xopiov,  chorion,  skin.] 
The  true  skin. 

CORN'E-A.  [L.  cornu,  a  horn.]  The 
transparent  membrane  in  the  fofe  part 
of  the  eye. 

COS'TA.  [L.  costa,  a  coast,  side,  or  rib.  | 
A  rih. 

CRIB'RI-FORM.  [L.  cribrum,  a  sieve, and 
forma,  form.]  A  »lat«  of  the  ethmoid 


454 


GLOSSY  RY 


hone,  through  which  the  olfactory  nerve 
passes  to  the  nooe. 

HKI'COID.  [Gr.  *p<*oj,  krikos,  a  ring, 
and  £((50f,  eidos,  form.]  A  name  given 
to  a  cartilage  of  the  larynx,  from  its  form. 

CRYS'TAL-LINE.  [L.  crystallinus,  con- 
sisting of  crystal.]  Crystalline  lens. 
One  of  the  humors  of  the  eye.  It  is 
convex,  white,  firm,  and  transparent. 

Cu'Bl-TUS,  -I.  [L.  cubitus,  the  elbow.] 
One  of  the  bones  of  the  forearm,  also 
called  the  ulna. 

Cu'BOlD.  [Gr.  «t)/?o? ,  kubos,  n  cube,  and 
ciSos,  eidos,  form.]  Having  nearly  the 
form  of  a  cube. 

CU-NE'I-FORM.  [L.  cuneus,  a  wedge.] 
The  name  of  bones  in  the  wrist  and  foot. 

CUS'PID.  [L.  cuspisy  a  point.]  Having 
one  point 

CU-TA'NE-OUS.  [L.  eutis,  skin.]  Be- 
longing to  the  skin. 

CU'TI-CLE.  [L.  cwtw.]  The  external 
layer  of  the  skin. 

CU'TIS  VE'RA.  [L.cutis,  and  vera,  true.] 
The  internal  layer  of  the  skin ;  the  true 
skin 

DEI/TOID.     [Gr.  JcXra,  delta,  the  Greek 

letter  A,  and  eidos,  etdos,  form.]    The 

name  of  a  muscle,  that  resembles  in 

form  the  Greek  letter  A. 
DENS.    [L.]    A  tooth. 
DENT'AL.    [L.  dens,  tooth.]    Pertaining 

to  the  teeth. 
DE-PRESS'OR.     [L.]     The  name  of  a 

muscle  that  draws  down  the  part  to 

which  it  is  attached. 
DERM'OID.     [Gr.  fop^a,  derma,  the  skin, 

and  £i<5o{,   tides,  form.]      Resembling 

skin. 
DE-SCEND'ENS.    [L.  de  and  seando,  to 

climb.]    Descending,  falling. 
Dl'A-PHRAGM.        [Gr.    timtppayna,   dia- 

phragma,  a  partition.]     The  midriff;  a 

muscle  separating  the  chest  from  the 

abdomen. 
DI-AR-RHGE'A.     [Gr.  imppew,  diarrhea, 

to  flow  through,]    A  morbidly  frequent 

evacuation  of  the  intestines. 
l»i-AS'TO-JLE      [Gr.  /cioTfAAw,  ditutcUo, 


to  put  asunder.]  The  dilatation  of  the 
heart  and  artems  when  the  blood 
enters  them. 

DI-GES'TION.  [L.  digestio.]  The  pro- 
cess of  dissolving  food  in  the  stomach, 
and  preparing  it  for  circulation  and 
nourishment. 

DIG-I-TO'RUM.  [L.  digitus,  a  finger.] 
A  term  applied  to  certain  muscles  of  the 
extremities. 

DOR'SAL.  [L.  dorsum,  the  back.]  Per- 
taining to  the  back. 

Du-o-DE'NUM.  [L,.  duodenus,  of  twelve 
fingers'  breadth.]  The  first  portion  of 
the  small  intestine. 

DU'RA  MA'TER.  [L.  durus,  hard,  and 
mater,  mother.]  The  outermost  mem- 
brane of  the  brain. 

DYS'EN-TER-Y.  [Gr.  <h>j,  dus,  bad,  and 
evrepta,  enteria,  intestines.]  A  dis- 
charge of  blood  and  mucus  from  the 
intestines  attended  with  tenesmus. 

DY&-PEP'SI-A.  [Gr.  6vs,  das,  bad,  and 
jreirrto,  pepto,  to  digest.]  Indigestion, 
or  difficulty  of  digestion. 

EN-AM'EL.      [Fr.]     The  smooth,  hard 

substance  which  covers  the  crown  or 

visible  part  of  a  tooth. 
EP-I-DERM'IS.     [Gr.  CTTI,  epi,  upon,  and 

fapua,    derma,  the    skin.]     Tht  scarf- 
skin  ;  the  cuticle. 
EP-I-GLOT'TJS.     [Gr.  f-m,  epi,  \\pon,  and 

yXurra,  fflottti,  the  tongue.]     One  of 

the  cartilages  of  the  glottis. 
EU-STA'CHI-AN  TUBE.    A  channel  from 

the  fauces  to  the   middle  ear,  named 

from  Eustachius,  who  first  described  it 
KX'CRE-MENT.  [L.  czcerno,  to  separate.] 

Matter    excreted    and  ejected ;    alvine 

discharges. 
EX-CRE-MEN-TI'TIAL.       Pertaining   tc 

excrement 
EX'CRE-TO-RY.    A  little  duct  or  vessel, 

destined  to  receive  secreted  fluids,  and 

to  excrete  or  discharge  them ;  also,  a 

secretory  vessel. 
Ex-HA'LANT.     [L.  exhalo,  to  send  forth 

vapor.]     Having  the  quality  of  exhaling 

or  evaporating 


GLOSSARY. 


455 


EX-TENS'OR.  [L.J  A  name  applied  to 
>»  muscle  that  serves  to  extend  any  part 
of  the  body  ;  opposed  to  Flexor. 

FA'CIAL.  [L.  fades,  face.]  Pertaining 
to  the  face. 

PALX.  [L.  falx,  a  scythe.]  A  process 
of  the  dura  mater  shaped  liki  a 
scythe. 

FAS'CI-A.  [L.  fascia,  a  band.]  A  ten- 
dinous expansion  or  aponeurosis. 

FAS-CIC'U-LUS,-LI.  [L.  fastis,  a  bundle.] 
A  little  bundle. 

FAUX,  -CES.    [L.]   The  top  of  the  throat. 

FEM'O-RAL.    Pertaining  to  the  femur. 

FEM'O-RIS.  A  term  applied  to  muscles 
that  are  attached  to  the  femur. 

FE'MUR.     [L.]     The  thigh-bone.    - 

FE-NES'TRA,  -UM.  [L.  fenestra,  a  win- 
dow.] A  term  applied  to  some  open- 
ings into  the  internal  ear 

Fl'BRE.  [L.  fibra.]  An  organic  fila- 
ment, or  thread,  which  enters  into  the 
composition  of  every  animal  and  vege- 
table texture. 

Fl'BRlN.  A  peculiar  organic  substance 
found  in  animals  and  vegetables  ;  it  is 
a  solid  substance,  tough,  elastic,  and 
composed  of  thready  fibres. 

FI'BROUS.  Composed  or  consisting  of 
fibres. 

FI'BRO-CAR'TI-LAGE.  An  organic  tis- 
sue, partaking  of  the  nature  of  fibrous 
tissue  and  that  of  cartilage. 

FiB'u-LA.  [L.,  a  clasp.]  The  outer  and 
lesser  bone  of  the  leg. 

FIB'U-LAR.    Belonging  to  the  fibula. 

FlL'A-MENT.  [L.  filamenta,  threads.] 
A  fine  thread,  of  which  flesh,  nerves, 
skin,  &c.,  are  composed. 

FLFC'TION.  [L.  flectio.]  The  act  of  bend- 
ing 

FOL'LI-CLE.  [L.  folhculus,  a  small 
bag.]  A  gland ;  a  little  bag  in  animal 
bodies. 

FORE'ARM.  The  part  of  the  upper 
extremity  between  the  elbow  and 
hand. 

FOS'SA  [L.,  a  ditch.]  A  cavity  in  a 
x>ne.  with  a  large  aperture 


FRjE'NUM.  [L.,  a  bridle.]  Fra-num  lin- 
gua. The  bridle  of  the  tongue. 

FUNC'TION.  [L.  funffor,  to  perform.] 
The  action  of  an  organ  or  system  oi 
organs. 

FUN'GI-FORM.  [L.  fungus  and  forma.} 
Having  terminations  like  the  head  tf  a 
fungus,  or  a  mushroom. 

GAN'GLI-ON,  -A.  [Gr.]  An  enlarge- 
ment in  the  course  of  a  nerve. 

GAS'TRIC.  [Gr.  j-aoriyp,  gastlr,  th« 
stomach.]  Belonging  to  the  stomach. 

GAS-TROC-NE'MI-US.  [Gr.  yaarrip,  gas- 
tSr,  the  stomach,  and  icyr/jur/,  knSml,  the 
leg.]  The  name  of  large  muscles  of 
the  leg. 

GEL'A-TIN.  [L.  gelo,  to  congeal.]  A 
concrete  animal  substance,  transparent 
and  soluble  in  water. 

GLE'NOID.  [Gr.  yXw,  glens,  a  cavity.] 
A  term  applied  to  some  articulate  cav 
ities  of  bones. 

GLOS'SA.  [Gr.]  The  tongue.  Names 
compounded  with  this  word  are  ap- 
plied to  muscles  of  the  tongue. 

GLOS'SO-PIIA-RYN'GI-AL.  Relating  to 
the  tongue  and  pharynx. 

GLOT'TIS.  [Gr.]  The  narrow  opening 
at  the  upper  part  of  the  larynx. 

GLU'TE-US.  [Gr.]  A  name  given  to 
muscles  of  the  hip. ' 

HEM'OR-RHAGE.  [Gr.  aipa,  haima,  blood 
and  priyvvw,  rSgnuo,  to  burst.]  A  dis- 
charge of  blood  from  an  artery  or  vein. 

Hu'MER-us.    [L..]    The  bone  of  the  arm. 

HY'A-LOID.  [Gr.]  A  transparent  mem- 
brane of  the  eye. 

HY'DRO-GEN.  [Gr.  iWcop,  water,  and 
•ytvvaw,  to  generate.]  A  gas  which  con- 
stitutes one  of  tlie  elements  of  water 

HY'GI-ENE.  [Gr.  vyicivov,  hugieinon, 
health.]  The  part  of  medicine  which 
treats  of  the  preservation  of  health. 

HY'OID.  [Gr.  v  and  c«  J«y,  eUos,  shape.] 
A  bone  of  the  tongue  resembling  the 
Greek  letter  upsiton  in  shape. 

HY-OID'E-US.  Pertaining  to  the  hyoid 
bone 


458 


GLOSSARY. 


HY'PO-GLOS'SAL.  Under  the  tongue. 
The  name  of  a  nerve  of  the  tongue. 

[L'E-UM.     [Or    £tXw,  eild,  to  wind.]     A 

portion  of  the  small  intestines. 
Ii/l-AC.     [Fiom  the  above.]    The  flank  ; 

pertaining  to  the  small  intestine. 
lL'l-UM.    The  haunch-bone. 
IN-CI'SOR.     |  L.  incido,  to  cut.]     A  front 

tooth  that  cuts  or  divides. 
I  N'DEX.     |  L.  indico,  to  show.]     The  fore- 
finger ;  the  pointing  finger. 
IN  NOM-I-NA'TA.  [L.  in,  not,  and  nomen, 

name.]    Parts  which  have  no  proper 

name. 
LN-OS'CU  LATE.     [L.  in  and   osculatus, 

from   oscular,  to  kiss.]      To  unite,  as 

two  vessels  at  their  extremitigteC 
IN'TER.    [L.]     Between. 
IN-TER-COST'AL.      [L.  inter,  between, 

and  costa,  a  rib.]     Between  the  ribs. 
IN-TER-NO'DI-I.    [L.  inter,  between,  and 

nodus,  knot.]     A  term  applied  to  some 

muscles  of  the  forearm. 
IN-TER-STI'TIAL.     [L.  inter,  between, 

and  sto,  to  stand.]    Pertaining  to  or  con- 
taining interstices. 
FN-TES'TINES.     [L.  intus,  within.]     The 

canal  that  extends  from  the  stomach  to 

the  anus. 
'RIS.    [L.,  the  rainbow.]    The  colored 

circle  that  surrounds  the  pupil  of  the 

eye. 
,'vo-ay.       A  hard,  solid,  fine-grained 

substance   of  a  fine  white  color ;    the 

tusk  of  an  elephant. 

JE-JU'NUM.     [L.,  empty.]     A  portion  of 

the  small  intestine. 
JU'GU-LAR.      [L.  jugulum,    the  neck.] 

Relating  to  the  throat     The  great  veins 

of  the  neck. 

LA'BI-UM,  LA'BI-I.    [L.]    The  lips. 

LAB'Y-RINTH.  [Gr."1  The  internal 
ear,  so  named  'rom  its  many  wind- 
ings. 

LACH'RY-MAL.  [L.  lackryma,  a  tear-.] 
Pertaining  to  tears. 

t.A<;'T£-Ai,.     fL.,   lar.,   milk  '      \   small 


vessel  or  tube  of  animal  bodies  for  con- 
veying  shyle  from  the  intestine  to  the 
thoracic  duct. 

LAM'I-NA,  -JE.  [L.]  A  plate,  or  thin 
coat  lying  over  another. 

LAR'YNX.  [Gr.  Au;>t'}(,  larunx.}  The 
upper  part  of  the  windpipe. 

LAR-YN-GI'TIS.  Inflammation  of  the 
larynx. 

LA-TIS'SI-MUS,  -MI.  [L.,  superlative  of 
lotus,  broad.]  A  term  applied  to  some 
muscles. 

LE-VA'TOK.  [L.  leva,  to  raise.]  A  name 
applied  to  a  muscle  that  raises  some 
part. 

LIG'A-MENT.  [L.  ligo,  to  bind.]  A 
strong,  compact  substance  serving  to 
bind  one  bone  to  another. 

LIN'E-A,  -JE.     [L.]     A  line. 

LIN'GUA,  -«.    [L.]     A  tongue. 

Liv'ER.  The  name  of  one  of  the  ab- 
dominal organs,  the  largest  gland  in  the 
system.  It  is  situated  below  the 
diaphragm,  and  secretes  the  bile. 

LOBE.  A  round  projecting  part  of  an 
organ. 

LON'GUS,  LON'GI-OR.  [L.,  long,  longer.] 
A  term  applied  to  several  muscles. 

LUM'BAR.  [L.  Iambus,  the  loins.]  Per- 
taining to  the  loins. 

LYMPH.  [L.  lymplta,  water.]  A  coler- 
less  fluid  in  animal  bodies,  and  con- 
tained in  vessels  called  lymphatics. 

LYM-PHAT'IC.  A  vessel  of  animal 
bodies  that  contains  or  conveys  lymph. 

MAG-NE'SI-UM.     The  metallic  base  of 

magnesia. 
MAG'NUS,  -NA,  -NUM.     [L.,  great.]     A 

term  applied  to  certain  muscles. 
MA'JOR.     [L.,  greater.]     Greater  in  ex- 
tent or  quantity. 
MAN'GA-NESE.    A  metal  of  a  whitish 

gray  color. 
MAR'ROW.    [Sax.]     A    soft,  oleaginous 

substance,  contained  in  the  cavities  of 

bones. 
MAS-SE'TER.  [Gr.  jaa<nra*aai, »»«»<"»»», 

to  chew.]    The  name  of  a  muscle  of 

the  face 


GLOSSARY. 


457 


MAS'TI-CATE,  MAS-TI-CA'TION.  LJU 
mastico.]  To  chew ;  the  act  of  chew- 
ing. 

MAS'TOID.  [Gr.  //aaros,  mastos,  breast, 
and  ei6os,  etdos,  form.]  The  name  of 
a  process  of  the  temporal  bone  behind 
the  ear. 

MAS-TOID'E-US.  A  name  applied  to 
muscles  that  are  attached  to  the  mas- 
toid  process. 

MAX-IL'LA.    fL.]    The  jaw-bone. 

MAX'IL-LA-RY.     Pertaining  to  the  jaw. 

MAX'I-MUS,  -UM.  [L.,  superlative  of 
magnus,  great.]  A  term  applied  to  sev- 
eral muscles. 

ME-A'TUS.  [L.  meo,  to  go.]  A  passage 
or  channel. 

ME-DI-AS-TI'NUM.  A  membrane  that 
separates  the  chest  into  two  parts. 

ME'DI-UM,  -A.  [L.]  The  space  or  sub- 
stance through  which  a  body  passes 
to  any  point. 

MED'UL-LA-RY.  [L.,  medutta,  marrow.] 
Pertaining  to  marrow. 

ME-DUL'LA  OB-LON-GA'TA.  Com- 
mencement of  the  spinal  cord. 

ME-DUL'LA  SPI-NA'LIS.  The  spinal 
cord. 

MEM'BRA-NA.  A  membrane;  a  thin, 
white,  flexible  skin  formed  by  fibres 
interwoven  like  net-work. 

MEM'BRA-NOUS.  Relating  to  a  mem- 
brane. 

MES'EN-TER-Y.  [Gr.  //e<ros,  meses,  the 
middle,  and  evrcpov,  enteron,  the  intes- 
tine.] The  membrane  in  the  middle 
of  the  intestines,  by  which  they  are 
attached  to  the  spine. 

MES-EN-TER'IC.  Pertaining  to  the  mes- 
entery. 

MET-A-CAR'PAL.  Relating  to  the  meta- 
carpus. 

MET-A-CAR'PUS.  [Gr.  uera,  meta,  after, 
and  /capirof,  karpos,  wrist]  The  part 
of  the  hand  between  the  wrist  and 
fingers 

MET-A-TAR'SAL  Relating  to  the  meta- 
tarsus. 

MET-A-TAR'SUS.  [Gr  uera,  meta,  after, 
Mid  rapao;,  taraos,  the  tarsus.]  The 

39 


instep.    A  term  applied  to  seven  boimo 

of  the  foot 
MID'RIFF.     [Sax.  mid,  and   hrtfe,  tbo 

belly.]     See  DIAPHRAGM. 
MIN'I-MUS,  -I.      [L.]     The  smallest.    A 

term  applied  to  several  muscles. 
MI'NOR     [L.]    Less,   smaller.    A  tern 

applied  to  several  muscles. 
MI'TRAL.      [L    mitra,  a   mitre.]    Th« 

name  of  the  valves  in  the  left  side  of 

the  heart. 
MO-DI'O-LUS.     [L.  modus,  a  measure.  | 

A  cone  in  the  cochlea  around  which 

the  membranes  wind. 
MO'LAR.      [L.  mola,  a  mill.]    The  name 

of  some  of  the  large  teeth. 
MOI/LIS.    [L.]    Soft. 
MO'TOR,  -ES.    [L.  moveo,  to  move.]    A 

mover.      A   term   applied   to   certain 

nerves. 

Mu'cous.    Pertaining  to  mucus. 
Mu'cus.    A  viscid  fluid  secreted  by  the 

mucous  membrane,  which  it  serves  to 

moisten  and  defend. 
MUS'CLE.    A  bundle  of  fibres  enclosed 

in  a  sheath. 

Mus'cu-LAR.    Relating  to  a  muscle 
MY-O'DES.    A  term  applied  to  certain 

muscles  of  the  neck. 

NA'SAL.    Relating  to  the  nose. 

NA'SUS.    [L.,  the  nose.]    The  nostrils. 

NERVE.  An  organ  of  sensation  and  mo- 
tion in  animals. 

NERV'OUS.    Relating  to  the  nerves. 

NEU-RI-LEM'A.  [Gr.  vcvpov,  neuron,  a 
nerve,  and  Xc/x/^a,  lema,  a  sheath.] 
The  sheath  or  covering  of  a  nerve. 

NI'GRUM.    [L.]    Black. 

NI'TRO-SEN.  That  element  of  the  air 
which  is  called  azote. 

NU-TRI'TION.  The  art  or  process  of 
promoting  the  growth,  or  repairing  the 
waste  of  the  system. 

OC-CIP-I-TA'LIS.    Pertaining  to  the  bach 

part  of  the  head. 
OC'CI-PUT.    [L.  ob  and  caput,  tie  head  • 

The  hinder  part  of  the  head. 
Oc-U-LO'RUM.    Of  the  eyw». 


458 


GLOSSARY. 


Oc'o-LUS,  -I.     [L.]    The  eye. 

CE-SOPH'A-GUS.  [Gr.  <HO>,  oiO,  to  carry, 
and  <[)ay<j),  pha^o,  to  eat.]  The  name 
of  the  passage  through  which  the  food 
passes  from  the  mouth  to  the  stomach. 

O-LEC'RA-NON.  [Gr.  wXeve,  dlene,  the 
cubit,  and  Kpavov,  kranon,  the  head.] 
The  elbow  ;  the  head  of  the  ulna. 

OL,-FACT'O-RY.  [L.  oleo,  to  smell,  and 
facio,  to  make.]  Pertaining  to  smell- 
ing. 

O-MEN'TUM     [L.]    The  caul. 

O'MO.  [Gr.  MHOS,  omos,  the  shoulder.] 
Names  compounded  of  this  word  are 
applied  to  muscles  attached  to  the 
shoulder. 

OPH-THAL'MIC.  [Gr.  o<f>9a\nos,  oph- 
thalmos,  the  eye.]  Belonging  to  the  eye. 

OP-PO'NENS  That  which  acts  in  oppo- 
sition to  something.  The  name  of  two 
muscles  of  the  hand. 

OP'TI-CUS,  OP'TIC.  [Gr.  orrro/tai,  op- 
tomai,  to  see.]  Relating  to  the  eye. 

OR-BIC'U-LAR.  [L.  orbis,  a  circle.] 
Circular. 

OR-BIC-U-LA'RIS.  A  name  applied  to 
several  muscles. 

OR'GAM.  A  part  of  the  system  destined 
to  exercise  some  particular  function. 

OR'I-GIN.    Commencement ;  source. 

Os.  [L.]  A  bone ;  the  mouth  of  any 
thing. 

O'Ris.     [L.  os,  oris.]     Of  the  mouth. 

Os  HY-OID'ES.  [Gr.  See  HYOID.] 
The  name  of  the  bone  at  the  base  of 
the  tongue. 

O3'MA-ZOME.  [Gr.  OCTM,  osmS,  smell, 
and  Cw/iioj,  zOr«os,  broth.]  A  principle 
obtained  from  animal  fibre  which  gives 
the  peculiar  taste  to  broth. 

OS'SA.     [L.,  pliuul  of  «s,  bone.]     Bones. 

OS'SE-OUS.     Pertaining  to  bones. 

OS-SI-FI-CA'TION.  The  formation  of 
bones  in  animals. 

OS'SI-FY.  [L.  ossa,  bones,  and  facio,  to 
make.]  To  convert  into  bone. 

Os'sis.    Of  a  bone. 

O-VA'LE.      [L.]     The  shape  of  an  egg. 

OX-AI/IO.  Pertaining  to  sorrel.  Oxalic 
acid  is  the  acid  of  sorrel  It  is  com- 


posed   of   two    equivalents   of  carbon 
and  three  of  oxygen. 
OX'Y-GEN.     A  permanently  elastic  mud 
invisible    and    inodorous.     One  of  the 
components  of  atmospheric  air 

PA-LA'TUM.  [L.]  The  palate ;  the  rooi 
of  the  mouth. 

PAL-PE-BRA'RUM.  [L.  palpebra,  the 
eyelid.]  Of  the  eyelids. 

PAL'MAR.  [L.  palma,  the  palm.]  Be- 
longing to  the  hand. 

PAL-MA'RIS.  A  term  applied  to  some 
muscles  attached  to  the  palm  of  the 
hand. 

PAN'CRE-AS.  [Gr.  wai/,  pan,  all,  and 
Kpeas,  kreas,  flesh.]  The  name  of  one 
of  the  digestive  organs. 

PAN-CRE-AT'IC.  Belonging  to  the  pan- 
creas. 

PA-PIL/LA,  -JE.  [L.J  Small  conical 
prominences. 

PA-RAL'Y-SIS.  Abolition  of  function 
whether  of  intellect,  sensation,  or  mo- 
tion. 

PA-REN'CHY-MA.  [Gr.  Tta^EY\cM,  pa- 
rengched,  to  pour  through.]  The  sub- 
stance contained  between  the  blood 
vessels  of  an  organ. 

PA-ROT'ID.  [Gr.  n-upa,  para,  near,  and 
euros,  5tos,  the  gen.  of  ovs,  oua,  the 
ear.]  The  name  of  the  largest  salivary 
gland. 

PA-TEL'LA,  -JE.    [L.J    The  knee-pan. 

PA-THET'I-CUS,-CI.  [Gr.  nuda^^patlios,, 
passion.]  The  name  of  the  fourth  paii 
of  nerves. 

PEC'TUS.     [L.]     The  chest 

PEC'TO-RAL..    Pertaining  to  the  chest 

PEC-TO-RA'LIS.    Belonging  to  the  chest. 

PE'DVS.  [L.,  gen.  of  pes,  the  foot.]  Of 
the  foot. 

PEL'I  TONGS.  A  term  applied  to  masses 
of  fat. 

PEL'LI-CLE.  [L.,  dim.  of  pellis,  ihe 
skin.]  A  thin  skin  or  film. 

PET/VIC.     Relating  to  the  pelvis. 

PEL'VIS.  [L.]  The  basin  formed  by 
the  large  bones  at  the  lower  part  of  the 
abdomen. 


GLOSSARY. 


459 


PEN'NI-FORM.  [L.  penna,  a  feather.] 
Having  the  form  of  a  feather,  or  quill. 

PER-I-CAR'DI-UM.  [Gr.  ii£pi,peri,  around, 
and  KapSta,  kardia,  the  heart.]  A  mem- 
brane that  encloses  the  heart. 

PER-I-CHON'DRI-UM.  [Gr.  nepit  peri, 
around,  and  xovJpo  j,cA<m<iros,cartilage.] 
A  membrane  that  invests  cartilage. 

PER-I-CRA'NI-UM.  [Gr.  nepi,  and  «pa- 
viov,  kranion,  the  cranium.]  A  mem- 
Imuie  that  invests  the  skull. 

PER'MA-NENT.    Durable ;  lasting. 

PER-I-STAL'TIC.  [Gr.  TrepiffrfAAw,  peri- 
stello,  to  involve.]  A  movement  like 
the  crawling  of  a  worm. 

PER-SPI-RA'TION.  [L.  per,  through,  and 
spiro,  to  breathe.]  The  excretion  from 
the  skin. 

PllAl/ANX,  -€TES.  [Gr.  <f>a\ay$,  phalanx, 
an  army.]  Three  rows  of  small  bones 
funning  the  fingers  or  toes. 

PIIA  LAN'GI-AL.  •  Belonging  to  the  fin- 
gers or  toes. 

PHA-RYN'GE-AL.  Relating  to  the  pha- 
rynx. 

PHAR'YNX.  [Gr.  <papuy£,  pharunx.]  The 
upper  part  of  the  oesophagus. 

PHOS'PHOR-US.  [Gr.  <£wj,  pfids,  the 
light,  and  0£pw,  phero,  to  bear.]  A  com- 
bustible substance,  of  a  yellowish  col- 
or, semi-transparent,  resembling  wax. 

PHREN'IC.  [Gr.  0pr?s/,  phrSn,  the  mind.J 
Belonging  to  the  diaphragm. 

PHYS-1-OL.'O-GY.  [Gr.  divans,  phusis, 
nature,  and  Aoyoj,  logos,  a  discourse.] 
The  science  of  the  functions  of  the 
organs  of  animals  and  plants. 

PI/A  MA'TER.  [L.,  good  mother.]  The 
name  of  one  of  the  membranes  of  the 
brain. 

PIG-MEN'TUM.  [L.J  Paint;  a  prepa- 
ration of  colors. 

PIN'NA.    [L.,  a  wing.]    A  part  of  the  ex- 
ternal ear. 
PL, A-T YS'MA.  [Gr.  TrAarus,  platfls,  broad.] 

A  muscle  of  the  neck. 
PLEU'RA,  -JR.    [Gr.  nXtvpa,  pleura,  the 
side.]     A  thin  membrane  that  covers 
the  inside  of  the  thorax,  and  also  forme 
the  exterior  coat  of  the  lungs. 


PLEU'RAL.    Relating  to  the  pleura. 

PLEX'US.  [L.  plecto,  to  weave  together  J 
Any  union  of  nerves,  vessels,  or  fibres, 
in  the  form  of  net-work. 

PNEU-MO-GAS'TRIC.  [Gr.  irvcv^wv,  pneu 
m5n,  the  lungs,  and  yaori/p,  gastSr,  the 
stomach.]  Belonging  to  both  the  stom- 
ach and  lungs. 

POL'LI-CIS.  fib]  A  term  applied  to 
muscles  attached  to  the  fingers  and  toes. 

PONS.  [L.]  A  bridge.  Pans  varolii. 
A  part  of  the  brain  formed  by  the  union 
of  the  crura  cerebri  and  cerebelli. 

POP-LIT-E'AL.  [L.  poples,  the  ham.] 
Pertaining  to  the  ham  or  knee-joint.  A 
name  given  to  various  parts. 

POS'TI-CUS.  [L.]  Behind ;  posterior 
A  term  applied  to  certain  muscles. 

POR'TI-O  DU'RA.  [L.,  hard  portion.J 
The  facial  nerve  ;  8th  pair. 

POR'TI-O  MOL'LIS.  [L.,  soft  portion.] 
The  auditory  nerve  ;  7th  pair. 

PO-TAS'SI-UM.  [L.]  The  metallic  basis 
of  pure  potash. 

PRO-BOS'CIS.  [Gr.  irpo,  pro,  before,  and 
/SoffKM,  boskd,  to  feed.]  The  snout  or 
trunk  of  an  elephant  or  other  animal. 

PROC'ESS.    A  prominence  or  projection. 

PRO-NA'TOR.  [L.  pronus,  turned  down- 
ward.] The  muscle  of  the  forearm 
that  moves  the  palm  of  the  hand  down- 
ward 

Pso'AS.  [Gr.  tl/oai,  psoai,  the  loins.] 
The  name  of  two  muscles  of  the  leg. 

PUL-MON'IC,         ^ 

PUL'MO-NA-RY,  C  [L.  pvlmo,  the  lungs. j 

PUL-MO-NA'LIS.  J 

Belonging  or  relating  to  the  lungs. 
PU'PIL.    A  little  aperture  in  the  centre 

of  the  iris,  through  which  the  rays  oi 

light  pass  to  the  retina. 
PY-LOR'IC.    Pertaining  to  the  pylorus. 
PY-LO'RUS.     [Gr.  ™Xwpoj,  pulSros,  a 

gate  keeper.]     The  lower  orifice  of  the 

stomach,  with   which   the.  duodenum 

connects. 

RA'DI-US.  |L.,  a  ray,  a  spoke  of  a 
wheel.]  The  name  of  one  >f  th« 
bonea  of  the  forearm. 


460 


GLOSSARY. 


RA-DI-A'LIS  Radial ;  belonging  to  the 
radius. 

RA'DI-ATE.  Having  lines  or  fibres  that 
diverge  from  a  point. 

RA'MUS.  [L.]  A  branch.  A  term  ap- 
plied to  the  projections  of  bones 

REORE-MEN-TI'TIAL.  [L.  re,  again, 
and  cerno,  to  secrete.]  Consisting  of 
superfluous  matter  separated  from  that 
which  is  valuable. 

REC'TUM.  The  third  and  last  portion  of 
the  intestines. 

REC'TUS, -I.  [L.J  Straight;  erect.  A 
term  applied  to  several  muscles. 

RE-SID'U-AL.  Pertaining  to  waste  matter. 

RE-SID'U-UM.  [L.]  Waste  matter.  The 
fzces. 

RES-PI-RA'TION.  [L.  re,  again,  and 
spiro,  to  breathe.]  The  act  of  breathing. 
Inspiring  air  into  the  lungs  and  expel- 
ling it  again. 

RE-SPI'RA-TO-RY.  Pertaining  to  respi- 
ration ;  serving  for  respiration. 

RET'l-NA.  [L.,rrte,a  net.]  The  essen- 
tial organ  of  sight.  One  of  the  coats 
of  the  eye,  formed  by  the  expansion  of 
the  optic  nerve. 

RO-TUN'DUM, -A.  [L.]  Round  ;  circular. 

Ru'OA,  -JK.    fL.]    A  wrinkle  ;  a  fold. 

SAC'CU-LUS.  [L.,  dim.  ofsacau,  a  bag.] 
A  little  sac. 

SA'CRAL.    Pertaining  to  the  sacrum. 

SA'CRUM.  [L.,  sacred.]  The  bone  which 
forms  the  posterior  part  of  the  pelvis, 
and  is  a  continuation  of  the  spinal 
column. 

BA-LI'VA.  [L.]  The  fluid  which  is 
secreted  by  the  salivary  glands,  which 
moistens  the  food  and  mouth. 

BAL'I-VA-RY.  That  which  belongs  to 
the  saliva. 

BAN'GUIN-E-OUS.  [L.  sanguis,  the  blood.] 
Bloody;  abounding  with  blood;  ple- 
thoric. 

BAR-TO'RI-US.  [L.  sartor,  a  tailor.]  A 
term  applied  to  a  muscle  of  the  thigh. 

BCA'LA,-JE.  [L.,  a  ladder.]  Cavities  »f 
the  cochlea 

[Gr.    viea\r}vos.    skalSnos, 


unequal.]      A    term    applied  to  si 
muscles  of  the  neck. 

SCAPH'OID.  |Gr.  aKaQn,  skaphl,  a  little 
boat.]  The  name  applied  to  one  of  tho 
wrist-bones. 

SCAP'U-LA.     [L.]      The  shoulder-blade 

SCAP'U-LAR.    Relating  to  the  scapula. 

SCARF-SKIN.  The  outer,  thin  integi- 
ment  of  the  body  ;  the  cuticle. 

SCI-AT'IC.  [Gr.,  pertaining  to  the  loins.". 
The  name  of  the  large  nerve  of  the 
loins  and  leg. 

SCLE-ROT'IC.  [Gr.  fficXripos,  sklSros, 
hard.]  A  membrane  of  the  eye. 

SE-BA'CEOUS.  [L.,  sebum,  tallow.]  Per- 
taining to  fat;  unctuous  matter. 

SE-CRE'TION.  The  act  of  secerning , 
the  act  of  producing  from  the  blood 
substances  different  from  the  blood  it- 
self, as  bile,  saliva.  The  matter  se- 
creted, as  mucus,  bile,  &c. 

SE-CRE'TO-RY.  Performing  the  office 
of  secretion. 

SE-CUN'DUS.  Second.  A  term  applied 
to  certain  muscles. 

SEM-I-CIR'CU-LAR.  Having  the  form  of 
a  half  circle.  The  name  of  a  part  of 
the  ear. 

SEM-I-TEN-DI-NO'SUS.  [L.  semi,  half, 
and  tendo,  a  tendon.]  The  nuoie  01 
a  muscle. 

SEP'TUM  [L.]  A  membrane  that  di 
vides  two  cavities  from  each  other. 

SE'ROUS.  Thin ;  watery.  Pertaining  tc 
serum. 

SE'RUM.  [L.]  The  thin,  transparent 
part  of  blood. 

SER-RA'TUS.  [L.serr0,tosaw.]  A  term 
applied  to  some  muscles  of  the  trunk. 

SIO'MOID.  fGr.]  Resembling  the  Greek 
j,  sigma. 

SI-LI'CI-UM.  A  term  applied  to  one 
of  the  earths. 

SI'NTJS.  [L.,  a  bay.]  A  cavity,  the  in- 
terior of  which  is  more  expanded  than 
the  entrance. 

SKEL'E-TON.  [Gr.  oxfAAw,  skelio,  to 
dry.]  The  aggregate  of  the  hard  parts 
of  the  body  ;  the  bones. 

SO'DI-UM.    The  metallic  base  of  soda 


GLOSSARY. 


461 


[Gr.  ffQiyyu,  sphingo,  to 
restrict.]  A  muscle  that  contracts  or 
shuts  an  orifice. 

SPI'NAL  CORD.  A  prolongation  of  the 
brain. 

SPI-NA'US.    Relating  to  the  spine. 

SPINE.  A  thorn.  The  vertebral  col- 
umn ;  back-bone. 

SPI'NOUS.  Belonging  to  the  spinal  col- 
umn. 

SPLEEN.  The  milt.  It  is  situated  in 
the  abdomen,  and  attached  to  the 
stomach. 

SPLEN'IC.    Relating  to  the  spleen. 

SPLE'NI-US.  The  name  of  a  muscle  of 
the  neck. 

STA'PES.  The  name  of  one  of  the 
small  bones  of  the  ear. 

STER'NUM.  The  breast-bone.  The  bone 
that  forms  the  front  of  the  chest  from 
the  neck  to  the  stomach. 

STOM'ACH.  The  principal  organ  of  the 
digestive  apparatus. 

STRA'TUM.  [L.  sterno,  to  stew.]  A 
bed  ;  a  layer. 

STY'LOID.  [L.  stylus,  a  pencil.]  An 
epithet  applied  to  processes  that  resem- 
ble a  style,  a  pen. 

SUB-CLA'VI-AN.  [L.  sub,  under,  and  da- 
vis,  a  key.]  Situated  under  the  clavicle. 

SUB-LI'MIS.    High  in  place. 

SUB-LIN'GUAL,.  [L.  sub,  under,  and 
'^iffua,  the  tongue.]  Situated  under 
tne  tongue. 

SUB-MAX'IL-L  A-RY.  [L.  sub,  under,  and 
rmzilla,  the  jaw-bone.]  Located  un- 
der the  jaw. 

SUL/PHUR.  A  simple,  mineral  substance, 
of  a  yellow  color,  brittle,  insoluble  in 
water,  but  fusible  by  heat. 

SU-PE-RI-O'RIS.  A  term  applied  to  cer- 
tain muscles. 

SU-PI-NA'TOR.  [L.]  A  muscle  that 
turns  the  palm  of  the  hand  upward. 

SUT'URE.  [L.swo,  to  sew.]  The  seam  or 
joint  that  unites  the  bones  of  the  skull. 

3YN-O'vi-A.  [Gr.  ffiu,  *Qn,  with,  and 
u>ov,  don,  an  egg.]  The  fluid  secreted 
into  the  cavities  of  joints  for  the  pur- 
pose of  lubricating  them. 


SYN-O'VI-AL.    Pertaining  to  synovii 

SYS'TEM.  An  assemblage  of  organs 
composed  of  the  same  tissues,  and 
intended  for  the  same  functions. 

SYS-TEM'IC.  Belonging  to  the  genera, 
system. 

SYS'TO-LE.  [Gr.  <7wr/AAw,  siixteMd,  to 
contract.]  The  contraction  of  the  heart 
and  arteries  for  expelling  the  blood  and 
carrying  on  the  circulation. 

TAR'SAL.    Relating  to  the  tarsus. 
TAR'SUS.    [L.]    The  posterior  part  of  the 

foot. 
TEN'DON.     [Gr.  rctvw,  teino,  to  stretch  ] 

A  hard,  insensible  oord,  or  bundle  of 

fibres,  by  which  a  muscle  is  attached 

to  a  bone. 

TEN'DI-NA,  -M.    Pertaining  to  a  tendon. 
TENS'OR.      A   muscle   that  extends    a 

part. 
TEN-TAC'U-LA,  -JR.    [L.  tento,  to  seize  ] 

A  filiform  process  or  organ  on  the  bodies 

of  various  animals. 
TEN-TO'RI-UM.    [L.  tendo,  to  stretch.] 

A  process  of  the  dura  mater  wh^h  lies 

between  the  cerebrum  and  cerebelluBi. 
TE'RES.    [L.  terts,  round.]    An  epithe'^ 

given   to  many   organs,  the  fibres  ol 

which  are  collected  in  small   bundles. 
THO'RAX.    [Gr.]    That  part  of  the  skel-  <' 

eton  that  composes  the  bones  of  the 

chest.     The  cavity  of  the  chest. 
THO-RAC'IC.    Relating  to  the  chest. 
THY'ROID.        [Gr.    dvpcos,    tfiureos,   a 

shield.]     Resembling  a  shield.     A  carti- 
lage of  the  larynx. 
TIB'I-A.    [L.,  a  flute.]    The  large  bone 

of  the  leg. 
TIB-I-A'LIS,  TIB'I-AL.     Relating  to  the 

tibia. 
TIS'SUE.     The  texture  or  organization 

of  parts. 
TON'SIL.     [L.]     A  glandular  body  in  th« 

throat  or  fauces. 
TRA'CHE-A.  [Gr  rpax^s,  traekus,  rough.] 

The  windpipe. 

TRA'CHE-AL.    Belonging  to  the  trachea 
TRANS-VERSE',TRANS-VER-SA'LIS.  Ly 

ing  in  a  cross  direction 


462 


GLOSSARY. 


FRA-PE'ZT-US.  The  name  of  a  muscle, 
so  called  from  its  form. 

FRI'CEPS.  [L.  tren,  three,  and  caput, 
head.]  Three.  A  name  given  to  mus- 
cles that  have  three  attachments  at  one 
extremity. 

TRI-CUS'PID.  [L.  tres,  three,  and  cu#pis, 
point.]  The  triangular  valves  in  the 
right  side  of  the  heart. 

TROCH'LE-A.  [Gr.  rpoxaXm,  trockalia, 
a  pulley.]  A  pulley-like  cartilage,  over 
which  the  tendon  of  a  muscle  of  the 
eye  passes. 

TROCH-LE-A'RIS.  The  name  of  a  mus- 
cle of  the  eye. 

TRUNK.  The  principal  part  of  the  body, 
to  which  the  limbs  are  articulated. 

Tu'BER-CLE.  [L.  tuber,  a  bunch.J  A 
small  push,  swelling,  or  tumor,  on  ani- 
mal bodies. 

TU-BER-OS'I-TY  The  state  of  being 
knobbed  or  protuberant. 

TYM'PAN-UM.     [L.]     The  middle  ear. 

UL'NA.    [L.]     A  bone  of  the  forearm. 
UL'NAR,  UL-NA'RIS.     Relating   to  the 

ulna. 
U'RIC.     [Gr.  ovpov,  ouron,  urine.]     An 

acid  contained  in  urine,  and  in  gouty 

concretions. 
U-VE'A.     [L.  uva,  a  grape.]     Resembling 

grapes.     A  thin  membrane  of  the  eye. 
IT'VU-LA.     A  soft  body,  suspended  from 

the  palate,  near   the    aperture  of  the 

nostrils,  over  the  glottis. 

VAC'CINE  VI'RUS.  [L.  -caeca,  a  cow, 
virus,  poison.]  Pertaining  to  cows  ; 
derived  from  cows. 

VALVE.  Any  membrane,  or  doubling 
of  any  membrane,  which  prevents  fluids 
from  flowing  back  in  the  vessels  and 
canals  of  the  animal  body. 

VAL'VU  LA,  -JR.     A  valve. 


VAS'CU-LAR.    [L.  vasculum,  a    vessel,  j 

Pertaining  to  vessels ;     abounding   in 

vessels. 
VAS'TUS.     [L.]     Great,  vast.     Applied 

to  some  large  muscles. 
VEINS.     Vessels  that  convey  blood   to 

the  heart. 

VE'NOUS.    Pertaining  to  veins. 
VEN'TRI-CLE.    [L.  venter,  the  stomach.] 

A  small  cavity  of  the  animal  body. 
VEN-TRIC'U-LAR.     Relating  to  ventri- 
cles. 
VER-MIC'U-LAR.    [L.  vermiculus,  a  little 

worm.]     Resembling  the  motions    f  a 

worm. 
VERM-J  FORM'IS.     [L.  vermis,  a  worm, 

and   forma,  form.]     Having    the   form 

and  shape  of  a  worm. 
VERT'E-BRA,  -JE.    [L.  verto,  to  turn.] 

A  joint  of  the  spinal  column. 
VERT'E-BRAL.    Pertaining  to  the  joints 

of  the  spinal  column. 
VES'I-CLE.     [L.  vesica,  a  bladder.]     A 

little  bladder,  or  a  portion  of  the  cuticle 

separated  from  the  cutis  vera  and  filled 

with  serum. 
VES'TI-BULE.    [L.J    A  porch  of  a  house. 

A  cavity  belonging  to  the  ear. 
VIL'H.    [L.J     Fine,  small  fibres. 
VI'RUS.    [L.,  poison.]     Foul  matter  of 

an  ulcer ;  poison. 
VI'TAL.     [L.   vita,   life.]     Pertaining  to 

life. 
VIT'RE-OUS.     [L.  vitrum,  glass.]     Be 

longing  to  glass.     A  humor  of  the  eye. 
VO'LAR.      [L.  vola,  the    hollow  of  the 

hand  or  foot.]     Belonging  to  the  palm 

of  the  hand. 
VO'MER.    [L.,  a  ploughshare.]    One  of 

the  bones  of  the  nose. 

ZYG-O-MAT'I-CUS.  [Gr.  $vyos,  zugos,  a 
yoke.]  A  term  applied  to  some  mus- 
cles of  the  face,  from  their  attachment, 


INDEX. 


A.                                    PAGE. 
ABDOMEN, 34 

ABSORPTION, 181 

,  Varieties  of, 183 

,  Cutaneous, 185 

ACETABULUM, 38 

ACIDS,  Acetic, 28 

,  Benzoic, 28 

,  Muriatic, 440 

,  Nitric, 440 

,  Oxalic, 28,   440 

,  Sulphuric, 440 

AIR,  Composition  of  the, 223 

,  Influence  of,  on  the  Muscles 90 

,  duality  of  the, 223,  3J8 

,  Quantity  inhaled, 222 

,  Quantity  "exhaled, 228 

,  Impure  Air,  the  Effects  of, 232 

AIR  VESICLES, 212 

ALBUMEN, 27 

ANIMAL  HEAT, 252 

AORTA, 159 

,  Valves  of  the, 157 

APPARATUS, 18 

ARTERIES,  Structure  of  the, 158 

,  Cutaneous, 285 

. ,  Pulmonary, 158 

ATTITUDE,  Effects  of,  on  Digestion,.  152 

,  Effects  of,  on  the  Voice,  274 

,  Effects  of,  in  Respiration  ,245 

AURICLES  of  the  Heart, 156 

ASPHYXIA,  from  Drowning, 249 

,  from  Electricity, 250 

,  from  Hanging, 250 

. -,  from  Carbonic  Gas, 251 


AZOTE,. 


B. 

BATHING,  Necessity  of 311 

,  Methods  oi         313 

,  Proper  Time  for, 316 

. ,  Influence  of,  on  the  Sys- 
tem,  316 

,  Frequency  of, 317 

RE  os, 309 

BILE, 122 

BLOOD,  Composition  of, 154 


BLOOD,  Color  of, y04 

,  Quantity  of, 171 

,  Change  of, 225 

,  Impure,  Effects  of, 205 

BONES,  Anatomy  of  thu, 29 

,  Physiology  of  the, 48 

,  Hygiene  of  the, 53 

of  the    Head, 32 

of  the  Trunk, 34 

of  the  Upper  Extremities, 39 

of  the  Lower  Extremities, 42 

,  Composition  of, 29 

,  Ossification  of, 30 

,  Union  of  fractured, 02 

,  Influence  of  Position  on  the,.  .55 

BRAIN, 329 

,  Functions  of  the, MG 

,  Effects  of  Impure  Plood  on  tiie,  300 

,  Effects  of  inadequate  Mental 

Exertion, 361 

,  Effects  of  excessive  .Mental 

Exertion, 363 

,  Directions  for  exercising  the,.  .368 

,  Membranes  of  the, 334 

,  Injuries  of  the, 377 

BRONCHIA, 219 

BRONCHITIS, .214 

BURNS  AND  SCALDS, 319 

BURSJE  MUCOSJE, 46 

e. 

CAECUM, US 

CAPILLARIES, 163 

CARBON, 26 

CARBONIC  GAS,  where  formed, 224 

— ,  Effects    of,    when 

inhaled, 330 

,  Effects  of,  on  Com- 
bustion,  230 

,  Effects  of,  on  Respi- 
ration,   231 

CARPUS, 41 

CARTILAGE, 45 

of  the  Larynx, 2f>9 


CAUL, 123 

CELLULAR  TISSUE, 19 

CEREBELLUM, .331 


464 


INDEX. 


PA  OK. 

CEREBRUM, 330 

CHEST, 35 

.  Compression  of  the, 56 

,  Influence  of  the  Size  of  the,.  .239 

CHILBLAINS, 321 

CHLORINE, 27 

CHYLE, 126 

CHYME, 126 

CIRCULATORY  ORGANS,  Anatomy, .154 

Physiology  of  the..  164 

Hygiene  of  the, ....  172 

CLAVICLE, 39 

CLOTHING,  Kind  of, 301 

,  Amount  of, 305 

,  Cleanliness  of, 308 

COCCYX, 38 

COLDS,  Treatment  of, 248 

COLON, 119 

CONSUMPTION,  how  frequently  pro- 
duced,   247 

CORNS,  Treatment  of, 295 

CUTICLE,  Structure  of  the 282 

,  Use  of  the, 293 

CUTIS  VERA,  Structure  of  the, 283 

D. 

DEFINITIONS,  General, 13 

DIAPHRAGM, 73,  215 

DIGESTIVE  ORGANS,  Anatomy  of  the,113 

,  Physiology  of  the,.. 124 

,  Hygiene  of  the, 129 

,  Influence    of    the 

Mind  on  the, 148 

,  Influence  of  Pure 

Air  on  the, 151 

,  Influence  of  Posi- 
tion on  the, 152 

DRINKS,  how  taken, 145 

DROWNED  PERSONS,  Treatment  of,. 249 
DUODENUM, 117 

E. 

EAR,  Bones  of, 34,  415 

EPIGLOTTIS, 125,  270 

EXH  AL  ANTS, 192 

EXERCISE,  how  it  should  be  taken,. .  .91 

,  Influence  of,  on  the  Bones,  53 

,  Influence  of,  on  Muscles,.  .85 

,  Influence  of  on  the  Cir- 
culation,   173 

KYE, 394 

LUPIRATION,  how  effected, 090 


F. 

PACE,  Bones  of  the, M 

FASCIA, 66 

PAT, 67,  195 

FEMUR, 42 

FIBRE, 18 

FIBRIN, 27 

FIBULA, 42 

FILAMENT, 18 

FLANNEL,  Use  of, 302 

FLUIDS,  Use  of, , 17 

FOLLICLE, 192 

FOOD,  Quantity  of  the, 125 

,  Quality  of  the, 134 

,  Manner  in  which  it  is  taken,. .  142 

,  Condition     of    the    system, 

when  taken, 148 

FOOT,  Bones  of  the, ^44 

FROZEN  LIMBS,  Treatment  of, 320 

O. 

GASTRIC  JUICE, 125 

GELATIN, 27 

GLANDS, 193 

,  Gastric, 1 J  6 

,  Lachrymal, 402 

,  Lymphatic, 1&3 

,  Mesenteric, 121 

,  Oil, 288 

,  Perspiratory, 290 

,  Salivary, 114 

GLOTTIS, 271 

H. 

HAIR, 322 

HEART, 154 

,  Auricles  of  the, 156 

,  Ventricles  of  the, 156 

HEAT,  Animal, 252 

,  Hygiene  of, 261 

HEARING,  Anatomy  of  the  Organs  of,  414 

,  Physiology  of  the  Organs 

of, 420 

,  Hygiene  of  the  Organs  of,. 422 

HUMERUS, 39 

HEMORRHAGE,  Means  of  arresting,..  175 
HYDROGEN, 26 

I. 

ILEUM, 118 

INTESTINES, 117 

fNNOMINATUM, 3^ 


INDEX. 


465 


INSPIRATION,  how  effected, 219 

IRON, 25 

J. 

JEJUNUM, 118 

JOINTS,  Structure  of  the, 45 


LACTE  ALS, 120,  181 

LAMINA, 17 

LARYNX, 268 

LARYNGITIS, 276 

LIGAMENTS, 23,  47 

,  Use  of, 50 

,  Capsular, 40 

LIGHT,  Influence  on  the  Skin, 318 

LIME, 25 

LIVER, 122 

LUNGS 209 

LYMPH, 30 

LYMPHATICS,  Anatomy  of  the, 181 

'-,  Physiology  of  the, 183 

,  Hygiene  of  the, 188 

,  Cutaneous 287 

m. 

MAGNESIA, 25 

MARROW,  Uses  of, 24 

MEDIASTINUM 211 

MEDULLA  OBLONGATA 333 

MEMBRANE, 19 

,  Adipose, 20 

,  Cellular, 19 

,  Dermoid, 22,  282 

. ,  Mucous, 31 

,  Muscular, 24 

,  Serous 21 

MESENTERY, 120 

METACARPUS, 41 

MOUTH,  Structure  of, 113 

Mucus, 28 

MUSCLES,  Anatomy  of, 64 

,  Physiology  of, 76 

,  Hygiene  of, 85 

.,  Compression  of, 93,  276 

,  Exhaustion  of, 87,  101 

-,  Effects  of  Pure  Blood  on,.. 89 
Effects  of  Pure  Air  on  the,. 90 

Effects  of  Light  on  the, 90 

Influence  of  the  Mind  on,.  .93 
Influence  of  Position  on, ..  96 


MUSCLES,  Intercostal,  ...............  214 

-  ,  Respiratory,  .............  216 


NAILS,  .............................  324 

NERVES,  Cranial,  ..............  335,  350 

-  ,  Cutaneous,  ................  286 


,  Respiratory, 340,  352 

,  Spinal, 341,  351 

,  Sympathetic, 343,356 

NERVOUS  SYSTEM,  Anatomy  of,.... 327 

,  Physiology   of,.. 346 

,  Hygiene  of, 358 

NITROGEN, 26 

NOSE,  Structure, 389 

NURSES,  Directions  for, 433 

NUTRITION, 200 

,  Hygiene  of, 205 


o. 

OESOPHAGUS, 116 

OIL-GLANDS,  Structure  of  the, 288 

,  Use  of  the, 297 


OME  NTU  M, 123 

ORGAN, 18 

ORGANIC  AND  INORGANIC  BODIES, 

Difference  between, 14 

ORIFICE,  Cardiac, 116 

,  Pyloric, 116 

OSMAZOME, 28 

OXYGEN, 26 

,  Quantity  at  each  Inspira- 
tion,  223 

P. 

PAPILLA, 284 

PANCREAS, 1:22 

PAROTID  GLAND, 114 

PATE  LLA, 42 

PERICARDIUM, I5c 

Pr.  K  IfHONDRIUM, 31 

PERICRANIUM, 31 

PERIOSTEUM, 31 

PELVIS,  Bones  of  the, 37 

PERSPIRATORY  APPARATUS, 290 

— Use  of,..  .298 


PHALANGES, 42,  45 

PHARYNX, 115 

PHOSPHORUS, 2fi 

PLEURA, 211 

POISONS,  and  their  Antidotes 43^ 


400 


INDEX. 


POTASH 25 

PRESERVATION  OF  HEALTH 425 

R. 

RADIUS, 41 

READING,  Proper  Position  in, 275 

RECTUM 120 

REMOVAL  OF  DISEASE, 426 

RESPIRATORY  ORGANS,  Anatomy  of,209 

,  Physiology  of,... 217 

,  Hygiene  of, 228 

RETINA, 397 

RIBS, 35 

ROOMS,  Ventilation  of, 233 

,  Wanning  of, 238 

S. 

SACRUM, 38 

SALIVA,  its  Use, 124 

SCAPULA, 39 

SECRETORY  ORGANS,  Anatomy  of,.  192 

,  Physiology  of.  193 

,  Hygiene  of,...  197 

SENSES, 378 

SICK-ROOM,  Ventilation  of, 236 

SITTING,  Proper  Position  in, 99 

SKELETON, 29 

SKIN,  Anatomy  of  the, 282 

,  Physiology  of  the, 293 

,  Hygiene  of  the, 301 

SKULL,  Structure  of, 32 

SLEEP,  Necessity  of,...' 92 

SLEEPING-ROOMS,  Ventilation  of,.. 235 
SHELL,  Anatomy  of  the  Organs  of,.  .389 

,  Physiology  of  the  Organs  of,.  .391 

SODA, 25 

So  LI  DS,  Arrangement  of, 17 

SOUND, 273 

SPINAL  COLUMN,  Structure  of, 3ti 

,  Curvature  of,. .  .57,  (50 

CORD, 36,  340 

SPLEEN, 123 

SPRAINS, 63 

STAMMERING,  how  improved, 281 

STERNUM, 35 

STOMACH, 116 

SUBLIXGUAL  GLAND, 115 

SUBMAXH.LARY  GLAND, 115 

SULPHUR, 26 

SUTTKES,. ..'33 


SYNOVIAL  MEMBRANE, 46 

SYNOVIA, 49 

SYSTEM, is 

T. 

TARSUS, 42 

TASTE,  Anatomy  of  the  Organs  of,  .  .384 
,  Physiology  of  ihe  Organs  of, .  .3a(j 


TEETH,  Anatomy  of  the, 105 

,  Physiology  of  the, 109 

,  Hygiene  of 'he, 110 


TENDONS, 23,  65 

THORACIC  DUCT, 120 

THORAX, 35 

THROAT,  Extraneous  Bodies  in, 281 

TIBIA, 42 

TISSUE  , 18 

,  Adipose, 20 

,  Cartilaginous, 23 

,  Fibrous, 22 

,  Osseous, 23 

,  Nervous, 24 

TOUCH,  Sense  of, 378 

,  Hygiene  of  the, 379 

TRACHEA, 212 

U. 

ULNA, 40 

UVE  A, 396 

V. 

VALVES  of  the  Heart, 157 

— ,  Use  of  the, 104 

of  the  Veins, 1C2 


VEINS, 100 

,  C""»ieou3, 285 

VENTII,        >N, 233 

VENTRI, 3  of  the  Heart, 156 

VERTEBRA, 36 

VISION,  Anatomy  "of  the  Organs  of,.  .394 

,  Physiology  of  the  Organs  of,.. 404 

,  Hygiene  of  the  Organs  of,... 410 


VOCAL  ORGANS,  Anatomy  of  the,... 268 

,  Physiology  of  the,.  .272 

,  Hygiene  of  the, 274 

VOCAL  CORDS, 270 

W. 

W ATCHE  RS,  Directions  for, 13(i 

WOI;>DS,  Treatment  of, 178 

WRITING,  Proper  Position  when. 103 


KEY    TO    ANATOMICAL    OUTL7NE    PLATfcS. 


KEY  TO  ANATOMICAL  OUTLINE  PLATES. 


SUGGESTIONS  TO  TEACHERS. 

Iir  using  these  plates,  we  would  suggest,  that  the  pupil  carefully  examine 
the  illustrating  cuts  interspersed  with  the  t^xt,  in  connection  with  th.e 
lesson  to  be  recited.  The  similarity  between  these  and  the  plates  will 
enable  the  pupil  to  recite,  and  the  teacher  to  conduct  his  recitation,  from 
the  latter. 

Let  a  pupil  show  the  situation  of  an  orgtw  ,  or  part,  on  an  anatomica, 
outline  plate,'  and  also  give  its  structure  ;  while  other  members  of  the  class 
note  all  omissions  and  misstatements.  Another  pupil  may  give  the  use  of 
that  organ,  and  if  necessary,  others  may  give  an  extended  explanation 
The  third  may  explain  the  laws  on  which  the  health  of  the  part  depends, 
while  other  members  of  the  class  supply  what  has  been  omitted.  Aftei 
thus  presenting  the  subject  in  the  form  of  topics,  questions  may  be  pro- 
posed promiscuously,  from  each  paragraph,  a'.d  where  examples  occur  in 
the  text,  let  other  analogous  ones  be  given. 

If  the  physiology  and  hygiene  of  a  given  subject  have  not  been  studied, 
confine  the  recitation  to  those  parts  only  on  which  the  pupil  is  prepared. 
When  practicable,  the  three  departments  should  be  united;  but  this  can 
only  be  done  when  the  chapter  on  the  hygiene  has  been  learned,  while 
the  physiology  can  be  united  with  the  anatomy,  in  all  chapters  upo;. 
physiology. 

PLATE  L  . 
A  FRONT   iEW  OF  THE  JKELETON. 


Bones  of  the  Head.  7,  The  sphenoid  bone.  8  The  frontal  bone.  10,  The 
parietal  bone.  11,  The  os  unguis.  12,  The  superior  maxillary  bone, 
(upper  jaw.)  13,  The  nasal  bone.  14,  The  ethmoid  bone.  15,  Themalai 
bone,  (cheek-bone.)  16,  The  vomer.  17,  The  inferior  maxillary  bone, 
(the  lower  jaw.)  a,  Its  body.  6,  Its  ramus,  or  branch.  18,  The  teeth. 

Bones  of  the  Trunk  1,  1,  The  spinal  column.  2,  The  sternum.  3,3,  Th*> 
ribs.  4,  The  sacrum.  5,  The  innominatum. 

Bones  of  tht,  Upper  Extremities.     19,  The  claT  .cle,  (collar-bone  )     20,  1  lie 


KEY    l'&    ANATOMICAL    OUTLINE    PLATES. 

scapula    (Shoulder  blade.)     21,  The  hnmerus.     22,  The  ulna       A>,    i'^s 
radius.    24,  25,  26,  27,  28,  29,  30,  81,  The  bones  of  the  carpus    (wrist. ) 

32,  32,  32,   The  five  bones  of  the  metacarpus,  (the  palm  of  the  hand.) 

33,  33,  33,  The  first  range  of  finger-bones.     34,  34,  The  second  range  of 
finger-bones.     35,  35,  35,  The  third  range  of  finger-bones. 

Bones  of  the  Lower  Extremities.  36,  The  femur,  (thigh-bone.)  37,  The 
patella,  (knee-pan.)  38,  The  tibia,  (shin-bone.)  39,  The  fibula.  40,  40, 
40,  The  bones  of  the  tarsus,  (instep.)  41,  41,  The  bones  of  the  metat&isua 
(middle  of  the  foot.)  42,  42,  The  bones  of  the  toes. 

ARTICULATIONS.     (Left  side  of  the  plate.) 

Ligaments  of  the  Trunk.  1,  1,  The  common  spinal  ligament.  2,  2,  The 
mtervertebral  ligament,  (cartilage  between  the  vertebrae.)  9,  10, 11, 12,  Ar- 
ticulations of  the  ribs  with  the  spinal  column.  13,  13,  14,  15,  16,  Liga- 
ments that  connect  the  cartilages  of  the  ribs  with  the  sternum. 

Ligaments  of  the  Upper  Extremities.  25,  The  ligament  that  connects 
the  clavicle  and  sternum.  27,  The  ligament  that  connects  the  upper  rib 
and  clavicle.  28,  29,  30,  Ligaments  that  connect  the  clavicle  and  scapula. 
31,  32,  33,  34,  Ligaments  of  the  shoulder-joint.  35,  35,  36,  Ligaments  of 
the  elbow-joint.  37,  38,  39,  40,  Ligaments  of  the  wrist.  41,  42,  43,  44, 
Ligaments  of  the  fingers. 

Ligaments  of  the  Lower  Extremities.  49,  49,  Ligaments  of  the  hip-joint. 
50,  50,  Ligaments  of  the  patella.  51,  52,  53,  54,  55,  Ligaments  of  the 
knee-joint.  56,  A  large  bursa  mucosa.  57,  The  ligament  of  the  tibia  and 
fibula.  58,  58,  The  interosseous  ligament.  59,  59,  Ligaments  of  the  an- 
kle-joint. 60,  61,  62,  Ligaments  of  the  metatarsus.  63,  64,  Ligaments  of 
the  toes. 

A,  The  brachial  artery.  B,  The  brachial  vein.  C,  The  radial  artery 
D  The  femoral  artery.  B,  xhe  femoral  vein.  F,  G,  The  anterior  tibia, 
artery.  v 

PLATE  H. 
A  BACK  VIEW  OF  THE  SKELETON. 

Bones  of  'the  Head.  5,  The  occipital  bone.  6,  The  parietal  bone.  7,  The 
temporal  bone.  8,  The  frontal  bone.  9,  The  sphenoid  bone.  15,  The 
malar  bone.  16,  The  nasal  bone.  17,  The  superior  maxillary  bone,  (upper 
jaw.)  18,  The  inferior  maxillary  bone,  (lower  jaw.)  19,  The  teeth. 

Bones  of  the  Trunk.  1,1,  The  spinal  column.  2,  The  sacrum.  3,  The 
coccyx.  20,  The  innominatum.  4,  4,  The  ribs. 

Bones  of  the  Upper  Extremities.  21,  The  clavicle,  (collar-bone.)  22,  The 
scapula,  (shoulder-blade.)  23,  The  humerus.  24.  The  ulna.  25,  The 
radius.  26,  27,  28,  29,  30,  31,  32,  The  bones  of  the  carpus,  (wrist.  } 
33,  33,  33,  The  bones  of  the  metacarpus,  (palm  of  the  hand.)  34,  34,  34 
The  first  range  of  finger-bones.  35,  35,  The  second  range  of  finger-bones 
:<H  3o.  36,  The  third  ranere  of  finger-bones. 


KEY    TO    ANATOMICAL    OUTL1I\E    PLATES. 

Bfmes  of  the  Lower  Extremities.  37,  The  femur,  (thigh-bone.)  38,  Th« 
patella,  (knee-pan.)  39,  The  tibia,  (shin-bone.)  40,  The  fibula.  41,  42, 
^3,  44,  45,  The  bones  of  the  tarsus,  (instep.)  46,  46,  The  bones  of  the 
metatarsus,  (middle  of  the  loot.)  47,  47,  Bones  of  the  toes. 

ARTICULATIONS.     (Left  side  of  the  plate.) 

Ligaments  of  the  Trunk.  1,  2,  3,  4,  5,  6,  7,  8,  9,  10,  Ligaments  of  the 
spinal  column.  14,  14,  15,  15,  Ligaments  that  connect  the  ribs  and  spinal 
column.  11,  11,  21,  22,  23,  24,  25,  26,  Ligaments  that  connect  the  sacrum 
and  innominatum. 

Ligaments  of  the  Upper  Extremities.  27,  28,  Ligaments  that  connect  the 
clavicle  and  scapula  29,  The  capsular  ligament  of  the  shoulder-joint. 
W,  30,  Ligaments  of  the  elbow.  31,  32,  33,  34,  Ligaments  of  the  carpus, 
(wrist.) 

Ligaments  of  the  Lower  Extremities.  9,  Tendon  of  the  gluteus  muscle 
35,  The  capsular  ligament  of  the  hip-joint.  36,  36,  Ligaments  of  the  knee- 
joint.  37,  The  ligament  that  connects  the  tibia  and  fibula  38,  The  in- 
.erosseous  ligament.  39,  40,  Ligaments  of  the  ankle-joint 


PLATE  m 
A  FRONT  VIEW  OF  THE  MUSCLES. 

Muscles  of  the  Head  and  Neck.  7,  The  sterno-mastoideus  muscle 
8,  The  sterno-hyoideus  muscle.  9,  The  omo-hyoideus  muscle.  10,  The 
trapezius  muscle.  11,  The  orbicularis  oculi  muscle.  12,  The  frontal 
muscle.  14,  The  orbicularis  oris  muscle.  15,  The  elevator  muscle  of  the 
nostrils.  16,  The  zygomatic  muscle.  17,  The  depressor  of  the  lower  lip 
18,  The  depressor  anguli  oris  muscle.  19,  The  triangular  muscle  of  the 
nose.  20,  21,  The  aural  muscles.  22,  The  masseter  muscle. 

Muscles  of  the  Trunk.     2,  3,  The  external  oblique  muscles. 

Muscles  of  the  Upper  Extremities.  1,  The  grand  pectoral  muscle. 
3,  4,  The  serratus  muscle.  23,  The  deltoid  muscle.  24,  The  biceps 
brachialis  muscle.  25,  The  coraco-brachialis  muscle.  26,  The  anterior 
orachial  muscle.  27,  The  triceps  brachialis  muscle.  28,  The  long  su- 
pinator  muscle.  29,  The  external  radial  muscle.  30,  The  pronator  teres 
muscle.  31,  The  anterior  radial  muscle.  32,  The  palmaris  brevis  musrlc. 
33,  The  anterior  ulnar  muscle.  35,  The  palmar  muscle.  36,  The  abductor 
muscle  of  the  thumb.  37.  The  adductor  muscle  of  the  thumb.  38,  39. 
Small  flexor  muscles  of  the  thumb.  40,  The  abductor  muscle  of  the  little 
finger.  41,  41,  The  lumbncales  muscles.  61,  61,  The  bifurcation  of  the 
tendons  of  the  superficial  flexor  muscle,  in  the  fingers. 

Muscles  of  the  Lower  Extremities.  42,  The  fascia  lata  muscle.  43,  The 
sartorius  muscle.  44,  The  rectus  femoris  muscle.  45,  The  vastus  externus 
muscle  4fi,  The  vastus  intornus  muscle.  47,  The  internal  straight  muscle 
48,  The  pectineus  nuisel*-.  49,  The  adductor  muscle.  oO.  Tlie  p.-."os 


KEY    TO    ANATOMICAL    OUTLINE    PLATES. 

muscle.  51,  The  tibialis  anticus  muscle.  52,  The  long  extensor  muscle 
of  the  great  toe.  53,  The  long  extensor  muscle  of  the  toes.  54,  The 
anterior  peroneal  muscle.  55,  The  long  lateral  peroneal  muscle.  56, 57,  The 
gastrocnemii  muscles.  58,  The  long  flexor  muscle  of  the  great  toe 
59,  The  short  extensor  muscles  of  the  toes.  60,  The  abductor  muscle  of 
the  great  toe. 

The  figures  and  letters  on  the  left  side  of  the  plate,  indicate  the  position 
of  important  fasciae,  that  cover  the  muscles  and  enclose  the  tendons. 


PLATE  IV. 

A  BACK  VIEW  OF  THE  MUSCLES. 

Muscles  of  the  Head  and  Neck.  4,  The  sterno-mastoideus  muscle 
5,  The  complexus  muscle.  6,  The  mylo-hyoideus  muscle.  7,  8,  The  cc- 
cipito-frontalis  muscle.  9,  The  masseter  muscle.  10, 11, 12,  The  anterior, 
middle,  and  posterior  aural  muscles.  13,  The  temporal  muscle. 

Muscles  of  the  Trunk.  1, 1,  The  trapezius  muscle.  2,  The  latissimus  dorsi 
muscle.  3,  The  rhomboideus  muscle.  4,  The  external  oblique  muscle. 

Muscles  of  the  Upper  Extremities.  5,  The  deltoid  muscle.  6,  7,  Tne 
infra-spinatus  muscle.  9,  The  triceps  extensor  muscle.  10,  The  internal 
brachial  muscle.  11,  The  long  supinator  muscle.  12,  The  external  radi- 
al muscle.  13,  The  second  external  radial  muscle.  14,  The  anconeue 
muscle.  15,  16,  The  extensor  digitorum  communis  muscle.  17,  The  ex- 
tensor carpi  ulnaris  muscle.  18,  The  flexor  carpi  ulnaris.  19,  20,  The 
extensor  ossis  metacarpi  pollicis  muscles.  21,  An  extensor  muscle  of  the 
thumb.  22,  28,  Interossii  muscles. 

Muscles  of  the  Lower  Extremities.  29,  The  gluteus  maximus  muscle 
30,  The  gluteus  medius  muscle.  31,  The  biceps  flexor  cruris  muscle. 
32,  The  semi-tendinosus  muscle.  33,  The  semi-membranosis  muscle. 
34,  The  gracilis  muscle.  35,  The  adductor  muscle.  36,  The  vastus  ex 
ternus  muscle.  37,  The  sartorius  muscle.  38,  39,  The  gastrocnemii 
muscles.  40,  The  long  peroneal  muscle.  41,  The  external  peroneal  mus- 
cle. 42,  The  long  flexor  muscle  of  the  great  toe.  43,  The  long  extensor 
muscle  of  the  toes.  44,  The  short  extensor  muscle  of  the  toes.  47,  The 
short  flexor  muscle  of  the  toes. 

The  figures  and  letters  on  the  left  side  of  the  plate,  indicate  the  position 
of  membranous  fasciae  which  envelop  the  muscles  and  tendons. 

PLATE  V. 

ORGANS  OF  THE  THORAX  AND  ABDOMEN. 

Fig.  1.  The  Mouth  and  Neck.  (A  Side  view.)  1,  The  upper  lip.  2,  The 
ewer  lip.  3,  Thenpporjaw.  4,  The  lower  jaw.  5,  The  tongue.  6,  The 
«ard  palate,  (roof  of  the  mouth.)  7,  The  parotid  gland.  8,  The  rub- 


KBY    TO    AiNATOMICAL    OUTLINE    PLATES. 

lingual  gland.     T,  The  larynx.     10,  The  pharynx.     11,  The  oesophagus 

12,  The  upper  portion  of  the  spinal  column.     C,  The  spinal  cord. 

The  Chest  and  its  Organs.  9,  9,  The  trachea.  R,  The  right  auricle 
of  the  heart.  L,  The  left  auricle.  13,  The  left  ventricle  of  the  heart. 
14,  The  right  ventricle.  15,  The  aorta.  16,  The  pulmonary  artery. 
17,  The  vena  cava  descendens.  18,  The  right  subclavian  vein.  19.  The 
left  snbclavian  vein.  20,  The  right  jugular  vein.  21,  The  left  jugular 
vein.  22,  The  right  carotid  artery.  23,  The  left  carotid  artery.  24,  25, 
26,  The  upper,  middle,  and  lower  lobes  of  the  right  lung.  27,  28,  The 
upper  and  lower  lobes  of  the  left  lung.  29,  29,  29,  The  diaphragm. 
P,  P,  P,  P,  The  pleura,  that  lines  the  cavity  of  the  chest.  S,  S,  The  clavi- 
des.  0,  0,  O,  O,  The  ribs.  M,  M,  M,  M,  Muscles  of  the  chest.  40,  The 
thoracic  duct,  opening  into  the  left  subclavian  vein. 

77«?  Abdomen  and  its  Organs.  30,  The  stomach.  31,  32,  The  right  and 
left  lobe  of  the  liver.  F,  The  fissure  that  separates  the  two  lobes.  33,  The 
gall  bladder.  34,  34,  The  duodenum.  35,  The  ascending  colon.  36,  The 
transverse  colon.  37,  The  descending  colon.  38,  38,  38,  38,  The  small 
intestine.  39,  39,  The  walls  of  the  abdominal  cavity  turned  down.  41, 
The  spleen. 

Fig.  2.  The  Relation  of  the  Lacteals  and  Thoracic  Duot.  1,  1,  A  section 
of  the  small  intestine.  2,  2,  2,  2,  2,  2,  2,  2,  Mesenteric  glands,  through 
which  the  lacteals  from  the  intestine  pass.  3,  Several  lacteal  vessels 
entering  the  enlarged  portion  and  commencement  of  the  thoracic  duct. 
5,  5,  5,  The  thoracic  duct.  6,  The  thoracic  duct  opening  into  the  left  sub- 
clavian vein.  7,  (See  40,  Fig.  1.)  8,  The  right  subclavian  vein.  9,  The 
Tena  cava  descendens.  10,  11,  11,  The  aorta.  12,  The  carotid  arteries. 

13,  13,  The  jugular  veins.     14,  The  vena  azagos.     15,  16,  The  spinal  col 
umn.     16,  The  diaphragm. 

Fig.  3.  The  Relation  of  the  Larynx,  Trachea,  Bronchia,  and  Air-cells. 
1,  1,  1,  An  outline  of  the  right  lung.  2,  2,  2,  An  outline  of  the  left  lung 
3,  The  larynx.  4,  The  trachea.  5,  The  right  bronchia.  6,  The  left  bron- 
chia. 7,  7,  7,  7,  Divisions  of  the  right  bronchia.  8,  8,  8, 8,  Divisions  of  the 
left  bronchia.  9,  9,  9,  9,  9,  9,  Air-cells. 

Fig.  4.     An  ideal  View  of  a  lateral  and  vertical  Section  of  the  Larynx. 

1,  ).  The  superior  vocal  cords,  (ligaments.)     2,  2,  The  inferior  vocal  cords. 
3,  ;-,  The  glottis.    4,  4,  The  ventricles  of  the  larynx. 

PLATE  VI. 
HEART,  ARTERIES,  AND  VEINS 

Fig.  i.     The.  Heart  and  large  Arteries.     1,   The  right  auricle  01  the  heart 

2.  The  right  ventricle  of  the  neart.     3,  The  left  auricle.     4,  The  left  ven- 
tricle,    o,  The  pulmonary   artery.     6,  The   aorta.     7,  7,  The   descending 

8,  The  arteria  innominata.     9.  The  left  carotid  artery.     10,  The  left 
ian  arleiy.     56,  The  right  subclavian  artery. 


KEY    TO    ANATOMICAL    OUTLINE    PLATE*.. 

Arteries  of  the  Neck  and  Head  15,  The  right  carotid  artery.  16,  The 
ieft  carotid  artery.  17,  The  right  temporal  artery.  50,  The  right  facial 
artery.  54,  The  left  temporal  artery. 

Arteries  of  the  Upper  Extremities.  11,  11,  The  left  brachial  artery. 
12,  The  left  radial  artery.  13,  13,  The  right  brachial  artery.  14,  The 
right  radial  artery.  51,  The  right  ulnar  artery. 

Arteries  of  the  Lower  Extremities.  18,  The  left  iliac  artery.  19,  The  right 
iliac  artery.  20,  The  left  femoral  artery.  21,  The  right  femoral  artery. 
22,  Theperoneal  artery.  23,  The  left  anterior  tibial  artery.  24,  The  mus- 
cular artery.  25,  25,  The  right  and  left  arteria  profunda.  26,  Thenght 
anterior  tibial  artery.  27,  The  right  peroneal  artery. 

The  Veins  of  the  Neck  and  Head.  28,  The  vena  cava  descendens 
29,  The  left  subclavian  vein.  30,  The  right  subclavian  vein.  31,  The 
right  jugular  vein.  32,  The  left  jugular  vein.  53,  The  right  temporal 
vein.  55,  The  left  temporal  vein.  49,  The  right  facial  vein. 

Veins  of  the  Upper  Extremities.  33,  The  left  brachial  vein.  34,  The  left 
radial  vein.  35,  The  right  brachial  vein.  36,  The  right  radial  vein 
51,  The  right  ulnar  vein. 

Veins  of  the  Lower  Extremities.  37,  The  vena  cava  ascendens.  38,  The 
eftiliacvein.  39,  The  right  iliac  vein.  40,  The  left  femoral  vein.  41,  The 
right  femoral  vein.  42,  The  left  anterior  tibial  vein.  43,  The  left  per- 
oneal vein.  44,  The  right  anterior  tibial  vein.  45,  The  right  peroneal 
vein.  46,  46,  The  profunda  veins.  47,  The  muscular  veins.  48,  48,  48, 
48,  48,  48,  Intercostal  arteries  and  veins. 

Fig.  2.  The  Relation  of  the  Cavities  of  the  Heart  to  the  large  Blood-vessels 
1,  The  vena  cava  descendens.  2,  The  vena  cava  ascendens.  3,  The  right 
auricle  of  the  heart.  4,  The  opening  between  the  right  auricle  and  right 
ventricle.  5,  The  right  ventricle.  6,  The  tricuspid  valves.  7,  The  pul- 
monary artery.  8,  8,  The  branches  of  the  pulmonary  artery  that  pass  to 
the  right  and  left  lung.  9,  The  semilunar  valves  of  the  pulmonary  artery. 
10,  The  left  pulmonary  veins.  11,  The  right  pulmonary  veins.  12,  The 
left  auricle.  13,  The  opening  between  the  left  auricle  and  left  ventricle. 
14,  The  left  ventricle.  15,  The  mitral  valves.  16,  16,  The  aorta.  17,  The 
aemilunar  valves  of  the  aorta.  18,  The  septum  between  the  right  and  left 
ventricle. 

Fig.  3.  An  ideal  View  of  the  Heart,  Arteries,  and  Veins.  A,  The  right 
auricle.  B,  The  right  ventricle.  C,  The  tricuspid  valves.  D,  The  open- 
ing between  the  right  auricle  and  right  ventricle.  E,  The  left  auricle 
F,  The  left  ventricle.  G,  The  mitral  valves.  H,  The  opening  between 
the  left  auricle  and  left  ventricle.  I,  The  septum  between  the  right  and 
left  ventricle.  K,  The  pulmonary  artery.  L,  The  semilunar  valves  of  thr 
pulmonary  artery.  M,  M,  The  right  pulmonary  artery.  N,  N,  The  left 
pulmonaiv  artery.  O,  O,  0,  O,  O,  0,  The  capillary  vessels  of  the  lungs 
P,  P,  P,  The  tight  pulmonary  vein.  Q,  Q,  The  Left  pulmonary  vein 
R,  R,  The  aorta.  S,  The  semilunar  valves  of  the  aorta.  T,  T,  A  branc> 
rtf  the  aorta  to  the  upper  extremities.  U,  U,  U  L,  A  branch  to  the  lower 
extremities.  V,  V,  V.  V,  V,  V,  The  capillary  vessels  at  the  extremity 


HEY    TO   ANATOMICAL    OTTTLiNE    FL/TEb. 

of    the    branches  of   the  aorta.     "W,   W,    The    descending  vena    cav». 
X,  X,  X,  The  ascending  vena  cava. 

In  Figs.  1,  2,  3,  the  course  of  the  blood  through  the  circulatory  vessels 
is  indicated  by  arrows. 

PLATE  VH. 
THE  PULMONARY  CIRCULATION. 

Fig.  1.  1,  The  right  auricle  of  the  heart.  2,  The  left  auricle.  3,  The 
right  ventricle  of  the  heart.  4,  The  left  ventricle.  5,  The  pulmonary 
artery.  6,  The  branch  of  the  pulmonary  artery  to  the  left  lung.  7,  The 
branch  of  the  pulmonary  artery  to  the  right  lung.  8,  8,  8,  8, 8,  8,  8,  8,  8,  8, 
Branches  of  the  pulmonary  artery  in  the  right  and  left  lung.  9, 9, 9,  9,  9, 9, 
Air-cells.  10,  10,  10,  10,  10,  10,  10,  Small  pulmonary  veins  in  the  right 
and  left  lung.  11,  The  left  pulmonary  vein.  12,  12,  The  right  pulmonary 
vein. 

Fig.  2.  An  ideal  View  of  the  Pulmonary  Circulation.  1,1,  The  right 
tung.  2,2,  The  left  lung.  3,  The  trachea.  4,4,4,  4,4,  The  right  bronchia. 
5,  5,  5,  5,  5,  The  left  bronchia.  6,  6,  6,  6,  6,  6,  Air-cells,  with  arteries  and 
veins  passing  around  them.  7,  The  right  auricle  of  the  heart.  8,  The 
right  ventricle  of  the  heart.  9,  The  tricuspid  valves.  10,  The  pulmonary 
artery.  11,  11,  11,  11,  The  right  pulmonary  artery.  12,  12,  12,  12, 12,  The 
left  pulmonary  artery.  13,  13,  13,  13,  The  right  pulmonary  vein. 
14, 14,  14,  14,  The  left  pulmonary  vein.  15,  The  left  auricle.  16,  The 
left  ventricle.  17,  The  mitral  valves.  18,  The  septum  between  the  light 
and  left  ventricles. 

Fig.  3.  An  ideal  View  of  the  Capillaries.  1,  1,  A  branch  of  the  pul- 
monary artery.  2,  2.  A  branch  of  the  pulmonary  vein.  3,  3,  Capillary 
vessels  between  the  artery  and  vein. 

Fig.  4.  An  ideal  View  of  the  Relations  of  the  Bronchia,  Air-cells,  Pul- 
monary Arteries,  and  Veins.  1,  A  bronchial  tube.  2,  2,  2,  Air-cells. 
3,  A  branch  of  the  pulmonary  artery.  4,  A  branch  of  the  pulmonary  vein. 


PLATE 

THE  CEREBRUM,  CEREBELLUM,  SPINAL  CORD,  AND 
NERVES. 

I,  The  cerebrum.    2,  The  cerebellum.    3,  3,  The  spinal  cord.    4,  The 
brachial  plexus  of  nerves.    5,  The  lumbar  plexus  of  nerves.    6,  The  sa- 
cral plexus  of  nerves.     7,   The   facial  nerve.      8,  17,  The  radial  nerve. 
9,  9,  16,  The  ulnar  nerve.     10,  The  median  nerve.     G,  The  circurarsx 
nerve  of  the  shoulder. 

II,  11,  The  great  sciatic  nerve.     12,  The  external  popliteal,  or  peroneaJ 


KKY     TO    ANATOMICAL    OUTLINE    PLATES*. 

nerve.  13,  13,  The  posterior  tibial  nerve.  14,  The  external  tibial  nervt» 
15,  The  muscular  branch  of  the  external  peroneal  nerve.  18,  The  muscu 
lar  branch  of  the  sciatic  nerve.  P,  Q,  The  posterior  tioial  nerve. 

The  letters  and  other  figures  indicate  minor  nervous  filaments   dis 
tributed  to  the  various  muscles  and  the  skin. 


PLATE  EX. 

THE  SKIN. 

Fig.  1.  A  perspiratory  Tube  and  Gland.  1,  1,  The  contorted  portion  of 
tLe  tube  that  forms  the  gland.  2,  2,  Two  branches  which  unite  to  form 
the  main  duct  of  the  gland.  3,  3,  The  perspiratory  tube.  4,  The  cuticle. 
6.  Its  colored  portion.  6,  The  cutis  vera,  (true  skin.)  7»  7,  Fat  vesicles, 
in  which  the  gland  is  imbedded. 

Fig.  2.  A  Papilla  of  the  Skin.  1,  1,  Two  papillae,  formed  of  an  artery 
veil.,  and  nerve.  2,  2,  2,  2,  Nerves  forming  a  loop  in  the  papillae.  3,  3,  Ar- 
teries of  the  papillae.  4,  4,  Veins  of  the  papillae.  5,  5,  A  net-work  of 
arteries,  veins,  and  nerves.  6,  6,  Nerves  of  the  skin.  8,  8,  Arteries  of 
the  skin.  7>  7,  Veins  of  the  skin. 

Fig.  3.  A  Hair,  audits  Oil-Glands.  1,  1,  The  hair.  2,  2,  The  sheath 
of  the  hair/  3,  Oil-glands  that  surround  the  bulb  of  the  hair,  the  ducts  of 
which  open  into  the  sheath  of  the  hair,  (2,  2.) 

Fig.  4.  A  Section  of  the  Skin.  1,  1,  The  cuticle.  2,  2,  Its  colored  por- 
tion. 3,  3,  The  papillary  layer.  4,  4,  A  net-work  of  arteries,  veins,  and 
nerves,  upon  the  upper  surface  of  the  cutis  vera.  5,  5,  5,  5,  The  cutis 
vera,  (true  skin.)  6,  6,  6,  Hairs  that  originate  in  the  cutis  vera.  7,  7, 7,  Oil- 
glands,  the  ducts  of  which  connect  with  the  sheath  of  the  hair.  8,  8,  8  8, 
8,  8,  8,  8,  Perspiratory  glands  and  their  ducts.  9,  9,  9,  9,  9,  Nerves  of  the 
skin  10,  10,  10,  10,  10,  Arteries  of  the  skin.  11,  11,  11,  11,  11,  Veins  of 
the  skin.  12,  12,  12,  12.  Papillae,  or  ridges  of  the  skin. 


PLATE   X. 
AN  ANTERO-POS1ER10R  SECTION   OF  THE  EYE. 

Fig.  1.  1,  1,  The  sclerotic  coat.  2,  2,  The  cornea.  3,  3,  The  choroid 
coat.  4,  4,  The  retina.  5,  5,  -The  iris.  6, 6,  The  posterior  chamber  of 
the  eye  that  contains  the  aqueous  humor.  7,  7,  The  anterior  chamber. 
8,  8,  The  pupil.  9,  The  crystalline  humor.  10,  10,  The  vitreous  humor 
11,  The  optic  nerve.  12,  A  representation  of  a  pen.  13,  An  inverted 
image  of  the  pen  (12)  on  the  retina.  14,  14,  A  canal  surrounding  the 
crystalline  humor.  15,  15,  The  bevelled  junction  of  the  cornea  and  scle 


K:'Y    T«    ANATOMICAL    OUTLINE    PLATES. 

totic  coats.     A,  a  perpendicular  ray  of  light  from  the  pen.     B,  B,  obliqu-e 
rays,  that  are  refracted  in  passing  through  the  humors  of  the  eye. 

Fig.  2.  A  View  of  the  External,  Middle,  and  Internal  Ear.  1,1.  The  ex- 
ternal ear.  2,  The  rueatus  auditorius  exteruus,  (the  tube  that  conneit-.i 
with  the  middle  ear.)  3,  The  membrana  tympani,  (drum  of  the  ear.) 
8,  8,  The  tympanum,  (middle  ear.)  4,  The  malleus  5,  The  incus. 
6,  The  orbicularis.  7,  The  stapes,  (stirrup-bone,)  that  connects  with  the 
vestibule  of  the  internal  ear.  9,  9,  (4,  5,  6,  7,  The  small  bones  of  the  mid- 
dle ear,)  10,  11,  12,  The  semicircular  canals.  13,  13,  The  cochlea. 
14,  The  auditory  nerve.  15,  The  division  of  the  auditory  nerve  to  thf 
Remicircular  canals.  16,  The  division  to  the  cochlea.  17,  17,  The 
Eustachian  tube.  18,  The  chorda  tympani  nerve.  19,  The  seventh  pair 
(facial)  nerve.  20,  The  styloid  process  of  the  temporal  bone.  21,  21 
21,  21,  21,  The  petrous  or  hard  portion  of  the  temporal  bone,  in  which 
the  parts  of  the  middle  and  internal  ear  are  situated. 


Be'trw  is.  eriven  the  Title  of  a  Book  on  a  new  plan,  just  published,  in 
tended  for  beginners  in  the  study  of  Physiology. 


HUMAN    AND    COMPARATIVE 


ANATOMY, 


PHYSIOLOGY,  AND  HYGIENE 


BT 

MRS.    EUNICE    P.    CUTTER. 


WITH  ONE  HUNDRED  ENGRAVLNGS. 


NEW    YORK: 
CLARR,   AUSTIN,   AND   SMITH 

3  PARK  Row 


TEXT  BOOKS 

UPON 

Anatomy,  Physiology,  and  Hygiene. 

Recommended  by  the  Hon.  If.  W.  EDWARDS,  School  Sup't,  111. 


H  VPT  i?03?v  ARATIVE   ANATOMY,  PHYSIOLOGY,  AND 

HYGIENE.     For  District  Schools.     With  100  Engravings.      132  pages. 
By  MRS.  EUNICE  P.  CUTTBH.     Price  33  cts. 

,  Th.«  w.ork  co"1'.'"?  ful1  directions  for  the  study  and  teaching  of  Anatomy,  Physiology, 
and  Hygiene.     This  is  a  new  feature.     Every  teacher  would  profit  by  it.     The  plan  of 
the  work  can  be  gathered  from  the  following  foe-simile  of  the  table  of  contents  :  - 

Preface,  ..............      6 

Introduction,  ........       8 

General  Analysis,  ----    10 

Teeth,  ..............    13 

Salivary  Glands,  .....    19 

Stomach,  .............    22 

Small  Intestine,. 


'STUDY  ME. 


CHAP.  I. 

DIGESTIVE 
SYSTEM. 


'  I  nm  fearfully  and 
wonderfully  made." 


CHAP.  II. 

RESPIRATORY 
SYSTEM. 

CHAP.  III. 

CIRCULATORY 

SYSTEM. 

CHAP.  IV. 

VOCAL   SYSTEM. 

CHAP.    I. 

CEREBRO-SPINAL 
SYSTEM. 


CHAP.  II. 

SENTIENT 
SYSTEM. 


CHAP.  I. 

OSSEOUS 
SYSTEM. 


CHAP.  II. 

MUSCULAR 
SYSTEM. 

CHAP.    III. 

CUTANEOUS 

SYSTEM. 


JLacteals, '. 30 

Large  Intestine, 32 

Synthetic   Review,...  35 

Thorax, 36 

Lungs, 39 

Pulmonary  Vessels,..  43 

Air, 45 

Synthetic  Review,....  48 

Heart, 50 

Pulmonic  Circulation,  53 

Systemic  Circulation,  56 

Synthetic  Review,....  58 

Vocal  organs, 61 

Synthetic  Review,....  64 


Brain, 67 

Spin'l  Cord  &  Nerves,    70 


Synthetic  Review, 


72 


Feeling, 73 

Taste, 74 

Smell, 75 

Seeing, 76 

Hearing, 80 

Synthetic  Review,...  84 

Head, 86 

Trunk, 89 

Upper  Extremities,  . .    93 
Lower  Extremities,..    97 

Joints, 101 

Composit'n  of  Bones,  105 
Synthetic  Review,....  108 

Muscles, 110 

Muscles,  continued,..  114 
Synthetic  Review,...  120 

Cuticle, ,  ..  122 

Cutis  Vera, 126 

Animal  Heat, 129 

Synthetic  Review,...  130 
General  Syn.  Review,  132 


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